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**Potential energy**

Potential energy, in other words, is called stored energy. There are many sorts of potential energy. Three main types of potential energy are gravitational potential energy, elastic potential energy, and chemical energy.

When you lift an object from the ground, it gains gravitational potential energy. Gravitational potential energy stays the same until the object is moved upwards or downwards. When the object is moved, the gravitational potential energy gets converted to other forms of energy, such as kinetic energy.

The gravitational potential energy equation is GPE = M x G x M denotes H. Mass, and G is the acceleration of free fall, which is universally accepted as 10 m/s^2. H is the height the object has gained.

Suppose a ball is lifted to a height of 5m and its mass is 4kg. What is the gravitational potential energy it has gained? Putting the values into the equation, GPE = 4 x 10 x 5 = 200 joules.

Suppose a fridge is lifted to a height of 6m and its mass is 40kg. What is the gravitational potential energy it has gained? Putting the values into the equation, GPE = 40 x 10 x 6 = 2400 joules.

Suppose an oven is lifted to a height of 7m and its mass is 12kg. What is the gravitational potential energy it has gained? Putting the values into the equation, GPE = 12 x 10 x 7 = 840 joules.

When a string is stretched, it stores energy in the form of elastic potential energy. The energy in the string remains unchanged until the length of the string is changed. The elastic potential energy equation is E = ½ x k x delta x^squared. K is the spring constant. And delta x is a change in extension.

Suppose a spring of 5m is stretched to 10m, and its spring constant is 0.5 N/m. What is the elastic potential energy stored in it? Putting the values into the equation, E = ½ x 0.5 x 5^2 = 6.25 joules.

Lastly, chemical energy is the energy stored in the bonds of chemical compounds. When we eat, we store energy in the form of chemical energy in our bodies. At the time of we do some work, suppose the chemical energy is converted to heat and kinetic energy.