Potential Energy

Potential Energy

The word potential energy was coined in the nineteenth century by William Rankine, a Scottish engineer and physicist, and it has a connection to the Greek philosopher Aristotle's concept of potentiality.

What is potential energy or what is the meaning potential energy? Or define potential energy class 9

Potential Energy Definition Physics: Potential energy meaning is the energy stored in an object is referred to as potential energy. Potential energy comes in a variety of forms, including gravitational potential energy, elastic potential energy, electric potential energy, and so forth. The gravitational potential energy is described as the energy that an object possesses as a result of its position in relation to other objects. Elastic potential energy is the energy possessed by an object as a result of tensions inside its body, while electric potential energy is the energy possessed by an object as a result of the entire charge stored within.

The most frequent types of potential energy are listed below.

  1. The gravitational potential energy is calculated as follows: The gravitational potential of an object is determined by its mass and distance from another object's center of mass (that can be large or small).
  2. The potential for elasticity: An extended spring's elastic potential energy, which transforms to kinetic energy when stretched from its mean position.
  3. An electric charge deposited in an electric field has an electric potential energy.

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Formula of potential energy-

Below is the formula for gravitational potential energy-

PE = mgh


  • PE is the object's potential energy in Joules, J
  • m is the object’s mass in kilogram,
  • g is the gravitational acceleration in ms-2, and
  • h is the object's height in meter with respect to the reference point.

Potential energy units-

The potential energy is represented by the letters U, V, or PE. The SI unit of potential energy is the Joule, which is represented by the letter ‘J' in English.

Dimension of potential energy-

M¹L²T⁻² is the dimension of potential energy.

Potential energy examples-

The following examples of potential energy statements demonstrate real-world uses of potential energy, and the relationship between potential and kinetic energy is also effectively explained:

  1. The energy stored in the water at the top of the waterfall (potential energy) is used to rotate the turbine and transform its kinetic energy into electricity.
  2. Newton's first law of motion, sometimes known as the law of inertia, is applied to a rubber band. It now expands and enlarges in length as you exert force on it. It's because the molecules inside the rubber band have previously saved energy, and when you apply force, all of the molecules start moving because they gain kinetic energy and the band extends.
  3. You take a bow and an arrow, and they both have energy stored in them at first. Now, as you extend the bow and release it, the arrow exits the bow and travels a great distance, depending on how much force we put. As a result, the action of our fingers converts this stored energy, or simply potential energy, into kinetic energy.
  4. You're lying in bed on a Saturday night of peaceful slumber, and you're in a free energy state, which means your energy is stored until someone wakes you up, such as an alarm clock or your phone ringing, at which point your stored energy transforms into dynamism or kinetic energy.
  5. When kinetic energy is applied to an AC generator, it begins to rotate around its axis in one of two directions: clockwise or counterclockwise. As a result, during a power outage in the residence, the energy stored in the generator is used to generate electricity.

Some other examples-

  1. When a child sits at the top of the swing, he has stored energy that becomes kinetic when he begins to slide down.
  2. An automobile in the parking lot has energy stored in it, and when it begins, the accelerator propels it forward.
  3. Unless it slides down the mountain to reach the ground, a vehicle standing at the top of the mountain possesses potential energy. As soon as the truck is started, it uses all of its stored potential energy to drag down the earth.

Relation between potential energy and kinetic energy-

In the previous example, we described the scenario of a truck climbing to the top of a mountain and then descending to the earth.

So it had stored energy at first, which was potential energy, and then it started going up the mountain, which was kinetic energy, so the total energy used by it was:

KEi + PEi.

As it approaches the bottom of the mountain, it has a potential energy, which turns to kinetic energy as it moves down the mountain. Now, in the final scenario, the total energy used is as follows:

KEf + PEf

As a result, the total energy used at the start equals the total energy used at the end. As a result, we want to build a relationship between kinetic and potential energy as follows:

KEi + PEi = KEf + PEf

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