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What is kinetic energy?

What are some ways in which the kinetic energy of an object is determined, which units of energy are commonly associated with kinetic energy.

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Kinetic energy is a form of energy that an object or a particle has by reason of its motion . If work , which transfers energy, is done on an object by applying a net force , the object speeds up and thereby gains kinetic energy. Kinetic energy is a property of a moving object or particle and depends not only on its motion but also on its mass .

Translational kinetic energy of a body is equal to one-half the product of its mass, m , and the square of its velocity , v , or 1/2 mv 2 .  For a rotating body the moment of inertia , I , corresponds to mass, and the angular velocity (omega), ω , corresponds to linear, or translational, velocity. Accordingly, rotational kinetic energy is equal to one-half the product of the moment of inertia and the square of the angular velocity, or 1/2 Iω 2 .

For everyday objects the energy unit in the metre-kilogram-second system is the joule. A 2-kg mass (4.4 pounds on Earth) moving at a speed of one metre per second (slightly more than two miles per hour) has a kinetic energy of one joule. The unit in the centimetre-gram-second system is the erg, 10 −7 joule, equivalent to the kinetic energy of a mosquito in flight . The electron volt is used on the atomic and subatomic scales.

kinetic energy , form of energy that an object or a particle has by reason of its motion . If work , which transfers energy , is done on an object by applying a net force , the object speeds up and thereby gains kinetic energy. Kinetic energy is a property of a moving object or particle and depends not only on its motion but also on its mass . The kind of motion may be translation (or motion along a path from one place to another), rotation about an axis , vibration , or any combination of motions.

Translational kinetic energy of a body is equal to one-half the product of its mass, m , and the square of its velocity , v , or 1 / 2 mv 2 .

This formula is valid only for low to relatively high speeds; for extremely high-speed particles it yields values that are too small. When the speed of an object approaches that of light (3 × 10 8 metres per second, or 186,000 miles per second), its mass increases, and the laws of relativity must be used. Relativistic kinetic energy is equal to the increase in the mass of a particle over that which it has at rest multiplied by the square of the speed of light .

The unit of energy in the metre - kilogram - second system is the joule . A two-kilogram mass (something weighing 4.4 pounds on Earth ) moving at a speed of one metre per second (slightly more than two miles per hour) has a kinetic energy of one joule. In the centimetre-gram-second system the unit of energy is the erg , 10 −7 joule, equivalent to the kinetic energy of a mosquito in flight. Other units of energy also are used, in specific contexts , such as the still smaller unit, the electron volt , on the atomic and subatomic scale.

For a rotating body, the moment of inertia , I , corresponds to mass, and the angular velocity (omega), ω , corresponds to linear, or translational, velocity. Accordingly, rotational kinetic energy is equal to one-half the product of the moment of inertia and the square of the angular velocity, or 1 / 2 Iω 2 .

The total kinetic energy of a body or a system is equal to the sum of the kinetic energies resulting from each type of motion. See mechanics: Rotation about a moving axis .

Kinetic Energy

Kinetic energy is a fundamental concept in physics that quantifies the work performed by an object due to its motion. It plays a crucial role in our understanding of various everyday activities such as walking, jumping, and throwing, as well as more complex phenomena like falling. In this article, we will delve into the concept of kinetic energy, exploring its definition, units of measurement, examples, and transformations. We will also derive the kinetic energy equation and examine its relationship with other forms of energy. Additionally, we will explore the different types of kinetic energy and discuss the distinction between kinetic and potential energy. By the end, you will have a comprehensive understanding of kinetic energy and its significance in the world around us.

What is Kinetic Energy?

Kinetic energy is a fundamental concept in physics that describes the energy transferred to an object due to its motion. In order to accelerate an object, force must be applied, which involves performing work. When work is done on an object, energy is transferred, resulting in the object moving with a new speed. This transferred energy is known as kinetic energy and is determined by the object’s mass and the speed it achieves.

According to the definition in physics, the kinetic energy of an object is the measure of the work it can do by virtue of its motion. It is important to note that kinetic energy is a scalar quantity , meaning it is solely described by its magnitude and does not have a directional component.

To summarise, kinetic energy is the energy associated with the motion of an object, obtained by performing work on it. It depends on both the mass of the object and the square of its speed. Understanding kinetic energy is crucial in comprehending various physical phenomena.

Units of Kinetic Energy

The units of kinetic energy are important in understanding and quantifying its measurement. In the International System of Units (SI), the standard unit for kinetic energy is the Joule (J) . One Joule is equivalent to 1 kilogram multiplied by metre squared divided by second squared (kg.m²/s²). This unit represents the amount of kinetic energy possessed by an object with a mass of 1 kilogram moving at a velocity of 1 metre per second.

In the CGS system (centimetre-gram-second), the unit of kinetic energy is the erg. One erg is defined as the amount of kinetic energy possessed by an object with a mass of 1 gram moving at a velocity of 1 centimetre per second.

Both the Joule and erg are derived from fundamental units of mass, length, and time, and they provide a standardised way to express and compare kinetic energy across different systems of measurement.

Kinetic Energy Examples

• A river flowing at a certain speed exhibits kinetic energy as the water possesses both velocity and mass.
• An asteroid falling towards Earth exhibits a tremendous amount of kinetic energy due to its large mass and high velocity.
• During flight, an airplane has a higher kinetic energy due to its substantial mass and fast velocity.
• The act of walking involves the movement of a person’s legs and body, resulting in the possession of kinetic energy.
• When a ball is thrown, it acquires kinetic energy while in motion through the air. The amount of kinetic energy it possesses is determined by the speed of the throw.
• Objects falling towards the ground accumulate kinetic energy due to the force of gravity. The impact’s kinetic energy is directly proportional to the object’s mass and velocity.
• A truck traveling down the road possesses greater kinetic energy compared to a car traveling at the same speed. This is because the truck has a significantly higher mass than the car.

Kinetic Energy Transformation

Kinetic energy can be transferred between objects and transformed into various other forms of energy . Let’s explore more examples of kinetic energy transformation.

Elastic Collision 

When two objects collide, such as two billiard balls, kinetic energy can be transferred between them. As the balls collide and rebound, some of the kinetic energy is transformed into other forms, such as heat and sound energy.

Pendulum Swing

As the pendulum swings back and forth, it undergoes a continuous transformation between potential and kinetic energy. At the highest point of the swing, the energy is mostly potential energy, and as it descends, the potential energy is converted into kinetic energy.

Car Braking

 When a car applies its brakes, the kinetic energy of the moving vehicle is transformed into other forms of energy, mainly heat energy. The friction between the brake pads and the wheels slows down the car by converting its kinetic energy into thermal energy.

Wind Turbine

 In a wind turbine, the kinetic energy of the moving air is harnessed and transformed into electrical energy. As the wind blows, it causes the blades of the turbine to rotate. The kinetic energy of the wind is converted into mechanical energy, which then drives a generator to produce electricity.

As water falls from a higher elevation in a waterfall, its potential energy is gradually transformed into kinetic energy. The flowing water gains speed and kinetic energy due to gravity, which can then be used to generate hydroelectric power.

Yo-Yo Transformation

A yo-yo provides an interesting demonstration of the transformation of kinetic energy. When a person holds a yo-yo in their hand, the yo-yo is at rest, and all the energy is stored in the ball in the form of potential energy. As the person releases the yo-yo, gravity pulls it downward, converting the potential energy into kinetic energy. The yo-yo ball accelerates as it descends, gaining speed and kinetic energy. At the bottom of the yo-yo’s path, the energy is entirely in the form of kinetic energy.

However, the transformation doesn’t end there. As the yo-yo reaches the end of its descent, it starts to climb back up due to the string’s tension. The kinetic energy of the yo-yo ball begins to transform back into potential energy as it gains height. The process repeats as the yo-yo moves up and down, with continuous conversions between potential and kinetic energy.

Kinetic Energy Formula

The formula of kinetic energy is an essential tool in understanding the energy associated with an object’s motion. The equation for kinetic energy is given by: \(\begin{array}{l}KE=\frac{1}{2}mv^{2}\end{array} \)

In this equation, KE represents the kinetic energy of the object. The symbol “m” refers to the mass of the object, while “v” represents its velocity.

The equation reveals that kinetic energy is directly proportional to both the mass and the square of the velocity of the object. This means that as either the mass or the velocity increases, the kinetic energy will increase as well. Moreover, the relationship between kinetic energy and velocity is particularly noteworthy because the velocity is squared in the formula. This implies that even small changes in velocity can have a significant impact on the kinetic energy of an object.

To calculate the kinetic energy of an object using this formula, you need to know the mass of the object and its velocity. First, square the velocity of the object, then multiply it by half of the object’s mass. The resulting value will give you the object’s kinetic energy.

Why is Kinetic Energy a Scalar Quantity?

Kinetic energy is a scalar quantity with no associated direction. It represents the magnitude of energy possessed by an object. While velocity, which is a vector quantity, has both magnitude and direction, the calculation of kinetic energy only considers the magnitude of velocity. The kinetic energy depends on the mass and the square of the magnitude of velocity. The squaring of the velocity term ensures that kinetic energy is always positive, regardless of the direction of motion . Therefore, even though velocity is a vector quantity, the calculation of kinetic energy focuses on magnitude, making it a scalar quantity.

Deriving Kinetic Energy Formula

The formula for calculating kinetic energy is an essential tool in understanding the energy associated with an object’s motion. The equation for kinetic energy is given by: \(\begin{array}{l} KE = \frac{1}{2} mv^2 \end{array} \) To begin, let’s consider a particle of mass “m” moving with a velocity “v.” The kinetic energy of this particle can be defined as the work done to accelerate the particle from rest to its current velocity. According to the work-energy theorem, the work done on an object is equal to the change in its kinetic energy.

The work done on the particle is given by the equation: \(\begin{array}{l} Work = Force\times Distance \end{array} \) (i) In the case of constant force, the work done can be calculated as: \(\begin{array}{l} Work = Force\times Distance \end{array} \) Now, let’s express the force in terms of mass and acceleration. According to Newton’s second law of motion, force (F) is equal to mass (m) multiplied by acceleration (a). Since the particle is moving with a constant velocity, its acceleration is zero. Therefore, the force acting on the particle is zero. Substituting the force into the work equation, we have: \(\begin{array}{l} Work =0\times Displacement \end{array} \) \(\begin{array}{l}Work= 0 \end{array} \) This means that no work is done on the particle as it moves with a constant velocity. Consequently, there is no change in its kinetic energy.

(ii) In the case when the particle is initially at rest and then accelerated to a final velocity “v” by an external force.

In this case, work is done on the particle to change its velocity.

The work done on the particle is equal to the change in its kinetic energy. So, we can write: \(\begin{array}{l}Work= Change\,in\,Kinetic\,Energy\end{array} \) Using the work formula: \(\begin{array}{l}Work = Force \times Displacement\end{array} \) The force acting on the particle is equal to the mass of the particle (m) multiplied by its acceleration (a). Since the initial velocity is zero, the final velocity is “v,” and the displacement is “d,” we have: \(\begin{array}{l}Work = (m \times a) \times d\end{array} \) Now, recall that the formula for acceleration (a) is given by: \(\begin{array}{l}a = \frac{Change\,in\,Velocity}{Time}\end{array} \) Since the initial velocity is zero, the change in velocity is “v” and the time taken is “t,” we can rewrite the equation as: \(\begin{array}{l}a =\frac{ v}{ t}\end{array} \) Substituting this back into the work equation, we have: \(\begin{array}{l}Work = (m × (v / t)) × d\end{array} \) \(\begin{array}{l}Work =(m \times v ) \frac{d}{t}\end{array} \) The quantity (d / t) represents the average velocity (v avg ) of the particle. So, we can rewrite the equation as: \(\begin{array}{l}Work = m \times v \times v_{avg}\end{array} \) Now, the average velocity (v avg ) is equal to half of the final velocity (v), as the particle starts from rest and reaches a final velocity “v.” Therefore, we can further simplify the equation as: \(\begin{array}{l}Work = m \times v \times (\frac{v}{2})\end{array} \) \(\begin{array}{l}Work = \frac{1}{2} \times m \times v^2\end{array} \) Finally, we equate the work done to the change in kinetic energy: \(\begin{array}{l}(\frac{1}{2}) \times m \times v^2 = Change\, in\,Kinetic\,Energy\end{array} \) Hence, we have derived the equation for kinetic energy: \(\begin{array}{l}K.E = (1/2) \times m \times v^2\end{array} \) This equation relates the kinetic energy (K.E) of an object to its mass (m) and velocity (v). It demonstrates that the kinetic energy is directly proportional to the square of the velocity and the mass of the object.

Kinetic Energy Calculation

1. Calculate the kinetic energy of a 200 kg object that is moving at a speed of 15 m/s. Solution:

The kinetic energy of the body can be calculated using the following equation:

Substituting the values in the above equation, we get

2. Calculate the mass of the object moving at a speed of 40 m/s and having a kinetic energy of 1500 J. Solution:

Rearranging the kinetic energy equation, we get

Substituting the values in the above equation, we get,

Types of Kinetic Energry

There are several types of kinetic energy that can be observed in different contexts. Some of the common types include:

Translational Kinetic Energy

This refers to the energy associated with the linear motion of an object. It is the most familiar type of kinetic energy and is observed when objects move in a straight line.

Rotational Kinetic Energy

This type of kinetic energy is exhibited by objects that are rotating or spinning around an axis. Examples include spinning tops, wheels, or rotating machinery.

Vibrational Kinetic Energy

Vibrational kinetic energy is related to the oscillatory motion of particles within a system. It is observed in vibrating strings, molecules, or atoms that are in a state of vibration.

Thermal Kinetic Energy

Thermal kinetic energy is associated with the random motion of particles within a substance. It is responsible for the temperature and heat transfer in a material. The faster the particles move, the higher the thermal kinetic energy.

Electrical Kinetic Energy 

Electrical kinetic energy is related to the movement of charged particles, such as electrons, in an electric current. It is utilised in various electrical devices and is a form of energy transfer.

These different types of kinetic energy demonstrate the wide range of phenomena where energy is associated with the motion of objects or particles. Each type of kinetic energy has unique characteristics and plays a role in different areas of physics and everyday life.

Overview of Kinetic Energy

Difference Between Kinetic Energy and Potential Energy

Read More: Difference between Kinetic and Potential Energy

For a more captivating exploration of kinetic energy and potential energy, we encourage you to watch the videos below. These videos delve into the concepts of kinetic energy and potential energy, unravelling their intricacies and showcasing their real-world applications.

Frequently Asked Questions – FAQs

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7.2 Kinetic Energy

Learning objectives.

By the end of this section, you will be able to:

• Calculate the kinetic energy of a particle given its mass and its velocity or momentum
• Evaluate the kinetic energy of a body, relative to different frames of reference

It’s plausible to suppose that the greater the velocity of a body, the greater effect it could have on other bodies. This does not depend on the direction of the velocity, only its magnitude. At the end of the seventeenth century, a quantity was introduced into mechanics to explain collisions between two perfectly elastic bodies, in which one body makes a head-on collision with an identical body at rest. The first body stops, and the second body moves off with the initial velocity of the first body. (If you have ever played billiards or croquet, or seen a model of Newton’s Cradle, you have observed this type of collision.) The idea behind this quantity was related to the forces acting on a body and was referred to as “the energy of motion.” Later on, during the eighteenth century, the name kinetic energy was given to energy of motion.

With this history in mind, we can now state the classical definition of kinetic energy. Note that when we say “classical,” we mean non-relativistic, that is, at speeds much less that the speed of light. At speeds comparable to the speed of light, the special theory of relativity requires a different expression for the kinetic energy of a particle, as discussed in Relativity .

Since objects (or systems) of interest vary in complexity, we first define the kinetic energy of a particle with mass m .

Kinetic Energy

The kinetic energy of a particle is one-half the product of the particle’s mass m and the square of its speed v :

We then extend this definition to any system of particles by adding up the kinetic energies of all the constituent particles:

Note that just as we can express Newton’s second law in terms of either the rate of change of momentum or mass times the rate of change of velocity, so the kinetic energy of a particle can be expressed in terms of its mass and momentum ( p → = m v → ) , ( p → = m v → ) , instead of its mass and velocity. Since v = p / m v = p / m , we see that

also expresses the kinetic energy of a single particle. Sometimes, this expression is more convenient to use than Equation 7.6 .

The units of kinetic energy are mass times the square of speed, or kg · m 2 /s 2 kg · m 2 /s 2 . But the units of force are mass times acceleration, kg · m/s 2 kg · m/s 2 , so the units of kinetic energy are also the units of force times distance, which are the units of work, or joules. You will see in the next section that work and kinetic energy have the same units, because they are different forms of the same, more general, physical property.

Example 7.6

Kinetic energy of an object.

• K = 1 2 ( 80 kg ) ( 10 m/s ) 2 = 4.0 kJ . K = 1 2 ( 80 kg ) ( 10 m/s ) 2 = 4.0 kJ .
• m = 2 K / v 2 = 2 ( 4.2 × 10 23 J ) / ( 22 km/s ) 2 = 1.7 × 10 15 kg . m = 2 K / v 2 = 2 ( 4.2 × 10 23 J ) / ( 22 km/s ) 2 = 1.7 × 10 15 kg .
• K = 1 2 ( 1.68 × 10 −27 kg ) ( 2.2 km/s ) 2 = 4.1 × 10 −21 J . K = 1 2 ( 1.68 × 10 −27 kg ) ( 2.2 km/s ) 2 = 4.1 × 10 −21 J .

Significance

Check your understanding 7.5.

(a) A car and a truck are each moving with the same kinetic energy. Assume that the truck has more mass than the car. Which has the greater speed? (b) A car and a truck are each moving with the same speed. Which has the greater kinetic energy?

Because velocity is a relative quantity, you can see that the value of kinetic energy must depend on your frame of reference. You can generally choose a frame of reference that is suited to the purpose of your analysis and that simplifies your calculations. One such frame of reference is the one in which the observations of the system are made (likely an external frame). Another choice is a frame that is attached to, or moves with, the system (likely an internal frame). The equations for relative motion, discussed in Motion in Two and Three Dimensions , provide a link to calculating the kinetic energy of an object with respect to different frames of reference.

Example 7.7

Kinetic energy relative to different frames.

• K = 1 2 ( 75.0 kg ) ( 1.50 m/s ) 2 = 84.4 J . K = 1 2 ( 75.0 kg ) ( 1.50 m/s ) 2 = 84.4 J .
• v PT = ( 15.0 ± 1.50 ) m/s . v PT = ( 15.0 ± 1.50 ) m/s . Therefore, the two possible values for kinetic energy relative to the track are K = 1 2 ( 75.0 kg ) ( 13.5 m/s ) 2 = 6.83 kJ K = 1 2 ( 75.0 kg ) ( 13.5 m/s ) 2 = 6.83 kJ and K = 1 2 ( 75.0 kg ) ( 16.5 m/s ) 2 = 10.2 kJ . K = 1 2 ( 75.0 kg ) ( 16.5 m/s ) 2 = 10.2 kJ .
• In a frame where v P = 0 , K = 0 v P = 0 , K = 0 as well.

Check Your Understanding 7.6

You are rowing a boat parallel to the banks of a river. Your kinetic energy relative to the banks is less than your kinetic energy relative to the water. Are you rowing with or against the current?

The kinetic energy of a particle is a single quantity, but the kinetic energy of a system of particles can sometimes be divided into various types, depending on the system and its motion. For example, if all the particles in a system have the same velocity, the system is undergoing translational motion and has translational kinetic energy. If an object is rotating, it could have rotational kinetic energy, or if it’s vibrating, it could have vibrational kinetic energy. The kinetic energy of a system, relative to an internal frame of reference, may be called internal kinetic energy. The kinetic energy associated with random molecular motion may be called thermal energy. These names will be used in later chapters of the book, when appropriate. Regardless of the name, every kind of kinetic energy is the same physical quantity, representing energy associated with motion.

Example 7.8

Special names for kinetic energy.

• The horizontal speed is (15 m)/(2 s), so the horizontal kinetic energy of the basketball is 1 2 ( 0.624 kg ) ( 7.5 m/s ) 2 = 17.6 J . 1 2 ( 0.624 kg ) ( 7.5 m/s ) 2 = 17.6 J .
• The average translational kinetic energy of a molecule is 1 2 ( 29 u ) ( 1.66 × 10 −27 kg/u ) ( 500 m/s ) 2 = 6.02 × 10 −21 J, 1 2 ( 29 u ) ( 1.66 × 10 −27 kg/u ) ( 500 m/s ) 2 = 6.02 × 10 −21 J, and the total kinetic energy of all the molecules is ( 3 × 10 23 ) ( 6.02 × 10 −21 J ) = 1.80 kJ . ( 3 × 10 23 ) ( 6.02 × 10 −21 J ) = 1.80 kJ .
• v = 2 ( 1.8 kJ ) / ( 0.624 kg ) = 76.0 m/s . v = 2 ( 1.8 kJ ) / ( 0.624 kg ) = 76.0 m/s .

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Kinetic Energy: Explanation, Review, and Examples

• The Albert Team
• Last Updated On: February 16, 2023

We’ve learned a lot so far about how and why things move. What we haven’t learned is what allows one object to exert a force on another. Energy is an important concept in physics that is used to understand large and small processes. Here, we’ll begin with the energy of a moving object by exploring examples of kinetic energy and how to calculate it. We’ll also dive into the differences between kinetic and potential energy.

What We Review

What is Kinetic Energy?

“Kinetic” and “energy” are both words we should be familiar with at this point. “Kinetic” comes up when discussing the friction of a moving object. “Energy” is one you’ve probably heard a lot in your life. It probably has a meaning similar to “the ability to do something” and that’s what it means in physics, too. We refine it a bit to mean the ability to do work or exert a force on an object over a displacement. From this, we can guess that kinetic energy should have something to do with things moving and their ability to exert a force. While that isn’t a perfect definition, it is fairly close.

Kinetic energy does, indeed, have to do with an object in motion. It is the energy an object has because of its motion and we can think of it in terms of the force that can be exerted on an object or the force it would take to stop the object. The way we want to think about this force will change in different situations. In general, though, the kinetic energy of a moving object can be thought of as a measure of how far the object’s velocity is from zero. The greater the velocity, the greater the energy.

Examples of Kinetic Energy

One familiar example of kinetic energy and how it changes depending on velocity could be walking versus running. It’s much harder to stop quickly when running at full speed than it is when walking slowly. The same applies to driving a car – the faster it’s going, the sooner the brakes need to be hit. This applies to our everyday lives but is also often built into video games. Have you noticed how much harder it can be to take a sharp turn in a racing game when driving at full speed than it is when slowing down? You have kinetic energy to thank for that.

How to Calculate Kinetic Energy

So far, we’ve been talking a lot about the velocity of a moving object relative to kinetic energy. While that is an important factor, there is another factor – mass. The mass of an object is a measure of its inertia, of how hard it is to change its motion. To find the kinetic energy of an object, then, we must account for both its velocity and its mass. These two values don’t have the same impact on the kinetic energy of a moving object, though.

Kinetic Energy Formula

The formula for kinetic energy is written as:

Here, the E_{K} symbol is used to represent kinetic energy, m represents the mass, and lastly v represents the velocity. We’ll work with this equation in just a moment, but first, there are two very important conceptual points to be made here. First, is that we haven’t seen this combination of values before, which means we have a new unit to work with. Energy is measured in Joules, which is denoted J. Second, the velocity is squared while the mass is not.

How Mass and Velocity Affect Kinetic Energy

Because the velocity has a higher exponent than the mass does, the velocity will have a larger impact on the kinetic energy of a moving object. For example, if the mass were to double the kinetic energy would also double, but if the velocity doubled the kinetic energy would be quadrupled. Similarly, if the mass were halved then the kinetic energy would be halved, but if the velocity were halved the kinetic energy would be quartered.

Examples of Calculating Kinetic Energy

Now that we know the equation, we can start using it to calculate kinetic energy. We’ll follow our normal problem-solving method to first find kinetic energy and then to find mass from kinetic energy and velocity.

Example 1: Finding Kinetic Energy from Mass and Velocity

A 6\text{ kg} bowling ball is rolling toward the pins at 7\text{ m/s} . What is the kinetic energy of the bowling ball?

• m=6\text{ kg}
• v=7\text{ m/s}
• E_{K}=\text{?}
• E_{K}=\frac{1}{2}mv^{2}

Example 2: Finding Mass From Kinetic Energy and Velocity

A flamboyance of flamingo flies at an average speed of about 17\text{ m/s} . If one of the flamingos has a kinetic energy of 430\text{ J} , what is its mass?

• v=17\text{ m/s}
• E_{K}=430\text{ J}

Differences Between Kinetic and Potential Energy

Kinetic energy is not the only important energy type in mechanical physics. The other energy you’re likely to encounter is potential energy. Both kinetic energy and potential energy are important to how we view and understand the world and there is one key difference between them.

What is Potential Energy?

Potential energy is the energy stored in an object that gives it the potential to do something. This is the energy in an object that is not moving or exerting a force, but it could. We often see this as gravitational potential energy – the potential to fall – or as spring potential energy – the potential to launch something with a spring. A more in-depth explanation of potential energy can be found in a separate post , but the important thing to remember is that potential energy is the potential to complete an action.

How Kinetic and Potential Energy Relate to Each Other

Kinetic energy is energy that comes from motion. Potential energy, on the other hand, is the energy an object has the potential to use for motion. These energies can be transformed into one another. Let’s consider an example of potential energy transforming into kinetic energy. Before jumping out of a plane, a skydiver has no kinetic energy but does have a lot of potential energy. Once they jump out of the plane, their potential energy will decrease as they get closer to the ground and that energy will be shifting into kinetic energy as the skydiver’s velocity increases. The skydiver’s kinetic energy will increase at the exact same rate that its potential energy decreases. The same would be true for any object whose potential energy is transforming into kinetic energy or for one whose kinetic energy is transforming into potential energy.

Mechanical energy is constantly present in our lives and it’s an important part of how we understand the universe. Kinetic energy can be found in any moving object and there are examples of kinetic energy in many aspects of daily life. It is far from the only type of mechanical energy you’ll learn about on your physics journey, but knowing how to identify and calculate kinetic energy will help as you continue to expand your knowledge of how and why objects behave as they do.

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Essay on Energy

Students are often asked to write an essay on Energy in their schools and colleges. And if you’re also looking for the same, we have created 100-word, 250-word, and 500-word essays on the topic.

Let’s take a look…

100 Words Essay on Energy

What is energy.

Energy is a fundamental concept in science. It’s what allows us to do work, move objects, and even think. There are many forms of energy, like kinetic, potential, thermal, and more.

Types of Energy

Kinetic energy is the energy of motion, while potential energy is stored energy. Thermal energy is related to heat, and chemical energy comes from chemical reactions.

Energy Conservation

Energy cannot be created or destroyed, only transferred or transformed. This principle is known as the law of conservation of energy. It’s why we must use energy wisely.

Renewable Energy

Renewable energy comes from sources that can be replenished. Solar, wind, and hydroelectric power are examples of renewable energy. These sources are important for a sustainable future.

250 Words Essay on Energy

Introduction.

Energy can be classified into two main categories: potential and kinetic. Potential energy is stored energy, like that held by a rock perched at the top of a hill. Kinetic energy, on the other hand, is energy in motion, like a rolling stone. These two forms can convert into each other, demonstrating the principle of energy conservation.

Energy Conversion and Conservation

The law of conservation of energy states that energy cannot be created or destroyed, only transformed. This principle governs everything from the smallest atomic particles to the largest galaxies. It also underpins the operation of all our machines and devices, which convert energy from one form to another.

Energy and Society

Energy is crucial to human society. We harness energy in various forms to power our homes, industries, and transport systems. The challenge of our time is to transition from fossil fuels, which are finite and damaging to the environment, to renewable sources like solar and wind energy.

In conclusion, energy is an essential concept that permeates every aspect of our lives. Understanding its nature, forms, and conservation principles can help us make informed decisions about its use and manage our resources sustainably for future generations.

500 Words Essay on Energy

Energy, in its myriad forms, is the cornerstone of our existence, powering everything from the smallest cellular processes to the most massive celestial phenomena. It is a fundamental concept in physics, representing the capacity to do work or cause change. Whether we look at the kinetic energy of a moving object, the potential energy stored by an object’s position in a force field, or the thermal energy due to an object’s temperature, we find that energy is the key driver of the universe.

Thermal energy, a form of kinetic energy at the microscopic level, is responsible for the temperature and phase changes of matter. Chemical energy, stored in the bonds of atoms and molecules, powers life on Earth and many of our technologies. Nuclear energy, harnessed from the nucleus of an atom, fuels our sun and provides a potent source of power for humanity.

The Law of Conservation of Energy

One of the fundamental principles governing energy is the Law of Conservation of Energy. This law states that energy cannot be created or destroyed, only converted from one form to another. This principle is a cornerstone of physics and has profound implications for our understanding of the universe. It underpins the concept of energy efficiency, the idea that we can optimize the use of energy by minimizing waste and maximizing output.

Energy and Sustainability

In conclusion, energy is a fundamental and ubiquitous concept, driving the processes of the universe and our daily lives. Understanding its various forms, the laws governing its behavior, and its role in sustainability is crucial. As we move forward, the challenge lies not only in harnessing energy more efficiently but also in doing so sustainably, ensuring the longevity of our planet and species.

That’s it! I hope the essay helped you.

Happy studying!

introduction

A system possesses energy if it has the ability to do work.

Energy is transferred or transformed whenever work is done..

• a scalar quantity
• abstract and cannot always be perceived
• given meaning through calculation
• a central concept in science

Energy can exist in many different forms. All forms of energy are either kinetic or potential. The energy associated with motion is called kinetic energy . The energy associated with position is called potential energy . Potential energy is not "stored energy". Energy can be stored in motion just as well as it can be stored in position. Is kinetic energy "used up energy"?

kinetic energy

• wind energy
• wave energy
• sound (sonic, acoustic) energy
• geothermal energy
• household current
• radio, microwaves, infrared, light, ultraviolet, x-rays, gamma rays
• solar energy

potential energy

• roller coaster
• hydroelectric power
• electric potential energy
• magnetic potential energy
• chemical potential energy
• elastic potential energy
• nuclear power
• nuclear weapons
• radioactive decay

English brewer and scientist James Joule (1818–1889) who determined the mechanical equivalent of heat.

Multitudinous

For those who want some proof that physicists are human, the proof is is the idiocy of all the different units which they use for measuring energy. Richard Feynman, 1965 (paid link)

Atomic and nuclear units

Another scheme

• ocean currents
• ocean thermal temperature gradients
• wood/charcoal
• natural gas

Historical Notes

• Aristotle of Stagira (384–322 BCE) Greece: first use of the word energeia ( ενεργεια ) in the Nicomachean Ethics . Its contemporary meaning has diverged significantly from Aristotle's original meaning. Aristotle's sense of the word is often translated as "activity" or "being at work". Energeia literally means "in work" or "to contain work", en+ergon ( εν+εργον ). In the Nicomachean Ethics , energeia was contrasted with hexis ( εξις ), which meant to "possess" or "to be in the state of". Energeia meant doing. Hexis meant possessing. Aristotle argues that virtue stems from actions and not merely from existence. These are terms of ethical philosophy, not science.

Τοῖς μὲν οὖν λέγουσι τὴν ἀρετὴν ἢ ἀρετήν τινα συνῳδός ἐστιν ὁ λόγος· ταύτης γάρ ἐστιν ἡ κατ᾽ αὐτὴν ἐνέργεια . διαφέρει δὲ ἴσως οὐ μικρὸν ἐν κτήσει ἢ χρήσει τὸ ἄριστον ὑπολαμβάνειν, καὶ ἐν ἕξει ἢ ἐνεργείᾳ . τὴν μὲν γὰρ ἕξιν ἐνδέχεται μηδὲν ἀγαθὸν ἀποτελεῖν ὑπάρχουσαν, οἷον τῷ καθεύδοντι ἢ καὶ ἄλλως πως ἐξηργηκότι, τὴν δ᾽ ἐνέργειαν οὐχ οἷόν τε· πράξει γὰρ ἐξ ἀνάγκης, καὶ εὖ πράξει. ὥσπερ δ᾽ Ὀλυμπίασιν οὐχ οἱ κάλλιστοι καὶ ἰσχυρότατοι στεφανοῦνται ἀλλ᾽ οἱ ἀγωνιζόμενοι (τούτων γάρ τινες νικῶσιν), οὕτω καὶ τῶν ἐν τῷ βίῳ καλῶν κἀγαθῶν οἱ πράττοντες ὀρθῶς ἐπήβολοι γίνονται. With those who identify happiness with virtue or some one virtue our account is in harmony; for to virtue belongs virtuous activity . But it makes, perhaps, no small difference whether we place the chief good in possession or in use, in state of mind or in activity . For the state of mind may exist without producing any good result, as in a man who is asleep or in some other way quite inactive, but the activity cannot; for one who has the activity will of necessity be acting, and acting well. And as in the Olympic Games it is not the most beautiful and the strongest that are crowned but those who compete (for it is some of these that are victorious), so those who act win, and rightly win, the noble and good things in life. Aristotle, ca. 320 BCE

• Dead force vis mortua .
• 1669 Dutch physicist Christiaan Huygens , vis viva or living force is conserved in perfectly elastic collistions
• 1689 German mathematician Gottfried Leibniz defined vis viva as mass times the square of velocity
• Émilie du Châtelet (1706–1749) France along with Voltaire (1694–1778) France.
• 1811 Italian mathematician Joseph Lagrange used calculus to show that a factor of two is involved in the relationship "potential" (potential energy) and vis viva (kinetic energy). As defined via the symbols used by Lagrange, i.e. T as kinetic energy, in his 1788 Analytical Mechanics
• "Hence is derived the idea conveyed by the term living or ascending force; for since the height to which a body will rise perpendicularly, is as the square of its velocity, it will preserve a tendency to rise to a height which is as the square of its velocity whatever may be the path into which it is directed, provided that it meet with no abrupt angle, or that it rebound at each angle in a new direction without losing any velocity. The same idea is somewhat more concisely expressed by the term energy , which indicates the tendency of a body to ascend or to penetrate to a certain distance, in opposition to a retarding force." Lecture V. On Confined Motion.
• "The term energy may be applied, with great propriety, to the product of the mass or weight of a body, into the square of the number expressing its velocity." Lecture VIII. On Collision.
• Carnot, changed his mind from the caloric to dynamic theory of heat but dies before he was recognised
• Coriolis, (re)defined work, travail, used calculus to propery derive KE as 1/2mv2, work equals change in energy, Du calcul d l'effet des machines.
• Joule, mechanical equivalent of heat
• "The object of the present communication is to call attention to the remarkable consequences which follow from Carnot's proposition, established as it is on a new foundation, in the dynamical theory of heat; that there is an absolute waste of mechanical energy available to man, when heat is allowed to pass from one body to another at a lower temperature, by any means not fulfilling his criterion of a "perfect thermo dynamic engine". As it is most certain that Creative Power alone can either call into existence or annihilate mechanical energy, the "waste" referred to cannot be annihilation, but must be some transformation of energy. To explain the nature of this transformation, it is convenient, in the first place, to divide stores of mechanical energy into two classes — statical and dynamical . A quantity of weights at a height, ready to descend and do work when wanted, an electrified body, a quantity of fuel, contain stores of mechanical energy of the statical kind. Masses of matter in motion, a volume of space through which undulations of light or radiant heat are passing a body having thermal motions among its particles (that is not infinitely cold), contain stores of mechanical energy of the dynamical kind."
• " Actual , or Sensible Energy , is a measurable, transmissible, and transformable condition, whose presence causes a substance to tend to change its state in one or more respects. By the occurrence of such changes, actual energy disappears, and is replaced by Potential or Latent Energy ; which is measured by the product of a change of state into the resistance against which that change is made. (The vis viva of matter in motion, thermometric heat, radiant heat, light, chemical action, and electric currents, are forms of actual energy; amongst those of potential energy are the mechanical powers of gravitation, elasticity, chemical affinity, statical electricity, and magnetism). The law of the Conservation of Energy is already known—viz., that the sum of all the energies of the universe, actual and potential, is unchangeable. The object of the present paper is to investigate the law according to which all transformations of energy, between the actual and potential forms, take place."
• 1855 potential and kinetic?
• When an eight-day clock has been wound up, it is thereby enabled to go for a week in spite of friction and the resistance which the air at every instant offers to the pendulum. It has got what in scientific language we call a supply of Energy. In this ense the energy simply consists in the fact of a mass of lead being suspended some four feet or so above the bottom of the clock-case. The mere fact of its being in that position gives it a power of "doing work" which it would not possess if lying on the ground. This is called Potential Energy .
• A 64 lb. shot, fired vertically from a gun loaded with an ordinary service charge of powder, would, if unresisted by the air, rise to about 35,000 feet, and if seizeed and secured at the highest point of its course, would possess there, in virtue of its position, a potential energy of 2,240,000 foot-pounds. When it left the gun it had none of this, but it was moving at the rate of fifteen hundred feet per second. It had KINETIC or (as it has sometimes been called) actual energy . We prefer the first term, which indicates motion as the form in which the energy is displayed. Kinetic energy depends on motion; and observation shows that its amount in each case is calculable from the mass which moves and the velocity with which it moves.

It’s a wonderful world — and universe — out there.

Come explore with us!  

Science News Explores

Explainer: kinetic and potential energy.

Let’s take a swing at clarifying the difference between these two types of energy 

Swings are a great example of potential energy switching into kinetic energy — and then back again. The little girl’s hair will even float for just a moment at the top of the swing’s arc.

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By Trisha Muro

February 17, 2023 at 6:30 am

When we talk with friends about energy, sometimes we’re talking about how tired or invigorated we feel. Other times we’re referring to how much charge is left in the battery on our phones. But in science, the word energy has a very specific meaning. It refers to the ability to perform some type of work on an object. That could be lifting the object off the ground or making it speed up (or slow down). Or it could be kick-starting a chemical reaction. There are lots of examples.  

Two of the most common types of energy are kinetic (Kih-NET-ik) and potential . 

Kinetic energy 

Every object in motion has kinetic energy. This could be a car zooming along the highway, a soccer ball flying through the air or a ladybug slowly walking along a leaf. Kinetic energy depends on just two quantities: mass and speed.  

But each has a different impact on kinetic energy.  

For mass, it is a simple relationship. Double something’s mass and you’ll double its kinetic energy. A single sock tossed toward the laundry basket will have a certain amount of kinetic energy. Ball up two socks and toss them together at the same speed; now you’ve doubled the kinetic energy. 

For speed, it’s a squared relationship. When you square a number in math, you multiply it by itself. Two squared (or 2 x 2) equals 4. Three squared (3 x 3) is 9. So if you take that single sock and throw it twice as fast, you’ve quadrupled the kinetic energy of its flight. 

In fact, this is why speed limits are so important. If a car crashes into a light post at 30 miles per hour (about 50 kilometers per hour), which might be a typical neighborhood speed, the crash will release a certain amount of energy. But if that same car is traveling 60 miles per hour (nearly 100 kilometers per hour), like on a highway, the crash energy hasn’t doubled. It’s now four times as high.  

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Potential energy

An object has potential energy when something about its position gives it the ability to do work. Usually, potential energy refers to the energy something has because it’s elevated above Earth’s surface. This could be a car at the top of a hill or a skateboarder at the top of a ramp. It could even be an apple that’s about to fall off a countertop (or tree). The fact that it’s higher than it could be is what gives it this potential to release energy when gravity lets it fall or roll down. 

An object’s potential energy is directly related to its height above Earth’s surface. Doubling its height will double its potential energy.  

The word potential hints that this energy has been stored up somehow. It’s ready for release — but nothing has happened yet. You can also talk about potential energy in springs or in chemical reactions. A resistance band you might use to exercise stores up the energy of your pull as you stretch it past its natural length. That pull stores energy — potential energy — in the band. Let go of the band and it will snap it back to its original length. Similarly, a stick of dynamite has a chemical type of potential energy. Its energy won’t be released until a fuse burns and ignites the explosive. 

Conservation of energy 

Sometimes kinetic energy becomes potential energy. Later, it may again turn back into kinetic energy. Consider a swing set. If you sit on a motionless swing, your kinetic energy is zero (you’re not moving) and your potential is at its lowest. But once you get going, you can probably sense the difference between the high and low points of your swing’s arc.  

At each high point, you stop just for a moment. Then you start swinging back down again. For that instant when you are stopped, your kinetic energy drops to zero. At that same point, your body’s potential energy is at its highest. As you swing back to the bottom of the arc (when you’re closest to the ground), it reverses: Now you’re moving your fastest, so your kinetic energy is also at its max. And since you’re at the bottom of the swing’s arc, your body’s potential energy is at its lowest.  

When two forms of energy switch places like that, scientists say that energy is being conserved.  

This isn’t the same thing as conserving energy by turning off the lights when you leave a room. In physics, energy is conserved because it can never be created nor destroyed; it just changes form. The thief that captures some of your energy on the swing is air resistance. That’s why you eventually stop moving if you don’t keep pumping your legs. 

If you hold a watermelon from the top of a tall ladder, it has quite a bit of potential energy. At that moment it also has zero kinetic energy. But that changes when you let go. Halfway to the ground, half of that melon’s potential energy has become kinetic energy. The other half is still potential energy. On its way to the ground, all of the watermelon’s potential energy will convert to kinetic energy.  

But if you could count up all of the energy from all of the tiny pieces of watermelon that explosively hit the ground (plus the sound energy from that SPLAT!), it would add up to the watermelon’s original potential energy. That is what physicists mean by conservation of energy. Add up all of the different types of energy from before something happens, and it will always equal the sum of all of its different types of energy afterward.  

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Kinetic and Potential Energy

Kinetic energy is energy possessed by a body by virtue of its movement . Potential energy is the energy possessed by a body by virtue of its position or state . While kinetic energy of an object is relative to the state of other objects in its environment, potential energy is completely independent of its environment. Hence the acceleration of an object is not evident in the movement of one object, where other objects in the same environment are also in motion. For example, a bullet whizzing past a person who is standing possesses kinetic energy, but the bullet has no kinetic energy with respect to a train moving alongside.

Comparison chart

Interconversion of Kinetic and Potential Energy

The law of conservation of energy states that energy cannot be destroyed but can only be transformed from one form into another. Take a classic example of a simple pendulum. As the pendulum swings the suspended body moves higher and due to its position potential energy increases and reaches a maximum at the top. As the pendulum begins its downward swing, the stored potential energy is converted into kinetic energy.

When a spring is stretched to one side, it exerts a force to the other side so it can come back to its original state. This force is called restoring force and acts to bring objects and systems to their low energy level position. The force required to stretch the spring is stored in the metal as potential energy. When the spring is released, the stored potential energy is converted into kinetic energy by the restoring force.

When any mass is lifted, the gravitational force of the earth (and the restoring force in this case) acts to bring it back down. The energy needed to lift up the mass is stored as potential energy due to its position. As the mass is dropped, stored potential energy is converted to kinetic energy.

The word "kinetic" is derived from the Greek word kinesis , which means "motion." The terms "kinetic energy" and "work", as understood and used today, originated in the 19th century. In particular, "kinetic energy" is believed to have been coined by William Thomson (Lord Kelvin) around 1850.

The term "potential energy" was coined by William Rankine , a Scottish physicist and engineer who contibuted to a variety of sciences, including thermodynamics .

Types of Kinetic Energy and Potential Energy

Kinetic energy can be classified into two types, depending on the type of objects:

• Translational kinetic energy
• Rotational kinetic energy

Rigid non rotating bodies have rectilinear motion. Thus translational kinetic energy is kinetic energy possessed by an object moving in a straight line. Kinetic energy of an object is related to its momentum (product of mass and velocity, p= mv where m is mass and v is velocity). Kinetic energy is related to momentum through the relation E = p^2 / 2m and hence translational kinetic energy is calculated as E = ½ mv^2. Rigid bodies which rotate along their center of mass possess rotational kinetic energy. Rotational kinetic energy of a rotating body is calculated as the total kinetic energy of its different moving parts. Bodies at rest also have kinetic energy. The atoms and molecules in it are in constant motion. The kinetic energy of such a body is the measure of its temperature.

Potential energy is classified depending on the applicable restoring force.

• Gravitational potential energy – potential energy of an object which is associated with gravitational force. For example, when a book is placed on top of a table, energy required to raise the book from the floor and energy possessed by the book due to its elevated position on the table is gravitational potential energy. Here gravity is the restoring force.
• Elastic potential energy – energy possessed by an elastic body like the bow and catapult when it is stretched and deformed in one direction is elastic potential energy. The restoring force is elasticity which acts in the opposite direction.
• Chemical potential energy – energy related to arrangement of atoms and molecules in a structure is chemical potential energy. Chemical energy possessed by a substance due to the potential it has to undergo a chemical change by taking part in a chemical reaction is chemical potential energy of the substance. When fuel is used, for example, chemical energy stored in fuel is converted to produce heat.
• Electrical potential energy – energy possessed by an object by virtue of its electric charge is electrical potential energy. There are two types – electrostatic potential energy and electrodynamic potential energy or magnetic potential energy.
• Nuclear potential energy – potential energy possessed by particles (neutrons, protons) inside an atomic nucleus is nuclear potential energy. For example, hydrogen fusion in the sun converts potential energy stored in solar matter into light energy.

Applications

• The roller coaster in an amusement park begins with the conversion of kinetic energy into gravitational potential energy.
• The gravitational potential energy keeps planets in orbit around the sun.
• Projectiles are thrown by a trebuchet making use of gravitational potential energy.
• In spacecrafts, chemical energy is used for take off after which the kinetic energy is increased to reach orbital velocity. Kinetic energy gained remains constant while in orbit.
• Kinetic energy given to cue a ball in a game of billiards is transferred to other balls through collisions.
• Wikipedia: Kinetic energy
• Wikipedia: Potential energy

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What Is Energy? Energy Definition and Examples (Science)

The concept of energy is key to science and engineering. Here is the definition, examples of energy, and a look at the way it is classified.

Energy Definition

In science, energy is the ability to do work or heat objects. It is a scalar physical quantity, which means it has magnitude, but no direction. Energy is conserved, which means it can change from one form to another, but isn’t created or destroyed. There are many different types of energy, such as  kinetic energy, potential energy , light, sound, and nuclear energy.

Word Origin and Units

The term “energy” comes from the Greek word  energeia  or from the French words  en meaning in and  ergon  which means work. The SI unit of energy is the joule (J), where 1 J = 1‎kg⋅m 2 ⋅s −2 . Other units include the kilowatt-hour (kW-h), British thermal unit (BTU), calorie (c), kilocalorie (C), electron-volt (EV), erg, and foot-pound (ft-lb).

What Losing Energy Means

One form of energy may be converted into another without violating a law of thermodynamics . Not all of these forms of energy are equally useful for practical applications. When energy is “lost”, it means the energy can’t be recaptured for use. This usually occurs when heat is produced. Losing energy doesn’t mean there is less of it, only that it has changed forms.

Energy may be either renewable or nonrenewable. Photosynthesis is an example of a process the produces renewable energy. Burning coal is an example of nonrenewable energy. The plant continues to produce chemical energy in the form of sugar, by converting solar energy. Once coal is burned, the ash can’t be used to continue the reaction.

Kinetic Energy and Potential Energy

The various forms of energy are classified as kinetic energy, potential energy, or a mixture of them. Kinetic energy is energy of motion, while potential energy is stored energy or energy of position. The total of the sum of the kinetic and potential energy of a system is constant, but energy changes from one form to another.

For example, when you hold an apple motionless above the ground, it has potential energy, but no kinetic energy. When you drop the apple, it has both kinetic and potential energy as it falls. Just before it strikes the ground, it has maximum kinetic energy, but no potential energy.

Renewable and Non-Renewable Energy

Another broad way of classifying energy is as renewable or non-renewable . Renewable energy is energy that replenishes within a human lifetime. Examples include solar energy, wind energy, and biomass. Non-renewable energy either does not regenerate or else takes longer than a human lifespan to do so. Fossil fuels are an example of non-renewable energy.

Forms of Energy

There are many different forms energy can take . Here are some examples:

• nuclear energy  – energy released by changes in the atomic nucleus, such as fission or fusion
• electrical energy  – energy based on the attraction, repulsion, and movement of electrical charge, such as electrons, protons , or ions
• chemical energy   – energy based on the difference between the amount required to form chemical bonds versus how much is needed to break them
• mechanical energy – the sum of the translational and rotational kinetic and potential energies of a system
• gravitational energy – energy stored in gravitational fields
• ionization energy – energy that binds an electron to its atom or molecule
• magnetic energy – energy stored within magnetic fields
• elastic energy – energy of a material that causes it to return to its original shape if it’s deformed
• radiant energy – electromagnetic radiation, such as light from the sun or heat from a stove
• thermal energy – kinetic energy due to the motion of subatomic particles, atoms, and molecules

Examples of Energy

Here are some everyday examples of energy and a look at the types of energy:

• Throwing a ball : Throwing a ball is an example of kinetic energy, potential energy, and mechanical energy
• Fire : Fire is thermal energy, chemical energy, and radiant energy. Its source may be either renewable (wood) or non-renewable (coal).
• Charging a phone battery : Charging a phone involves electrical energy, chemical energy (for the battery), and both kinetic and potential energy. The stored electrical charge is potential energy, while moving charge is kinetic energy.
• Harper, Douglas. “Energy”.  Online Etymology Dictionary .
• Smith, Crosbie (1998).  The Science of Energy – a Cultural History of Energy Physics in Victorian Britain . The University of Chicago Press. ISBN 978-0-226-76420-7.

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Stemonstrations: kinetic and potential energy.

Grade Levels

Grades 5-8, Grades 9-12

Physical Science, Technology, Energy, Space Station

Lesson Plans / Activities, Videos

Watch NASA astronaut Joe Acaba demonstrate kinetic and potential energy on the International Space Station by showing how an object’s potential energy changes due to its position. How can potential energy be converted into kinetic energy?

Classroom Connection: Kinetic and Potential Energy

Grade Level: 6-12

Time Required: 50 minutes

Next Generation Science Standards:

HS-PS3-1. Construct and interpret graphical displays of data to describe the relationships of kinetic energy to the mass of an object and to the speed of an object.

MS-PS3-1. Create a computational model to calculate the change in the energy of one component in a system when the change in energy of the other component(s) and energy flows in and out of the system are known.

MS-PS3-2. Develop a model to describe that when the arrangement of objects interacting at a distance changes, different amounts of potential energy are stored in the system.