## Potential Energy

### Introduction

• It is the energy of an object due to the virtue of its position, configuration and orientation.
• It is denoted by 'u'.
• There are various types of potential energy.

#### Examples of Potential Energy:

1. Water stored in dams contain potential energy.
2. Elongated or compressed spring also has potential energy.
3. Objects placed at a height contain potential energy.
4. Two charged particle separated at a distance contain potential energy.

### Gravitational Potential Energy

It is the energy of an object due to its position. Its value is taken as 0 on the surface of the earth. It is given by a formula:

u = mgh

u is the potential energy.
m is the mass of the object.
g is the acceleration due to gravity.
h is the height of an object.

#### Expression:

work = force * displacement
w = mg * h
(as work = potential energy)
Gravitation al Potential Energy = mgh

#### Factors affecting gravitational potential energy:

1. It is directly proportional to the mass of the object.
2. It is directly proportional to the height of the object.
3. It is directly proportional to the acceleration due to gravity.

### Elastic Potential Energy

It is the energy related to spring or elastic chord.
Elastic potential energy is given by a formula:
u = 1/2 k x^2
u is the energy
k is constant
x is displacement of spring

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