Energy

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Define energy.

Energy is the capacity to perform a given task. Energy can be either potential or kinetic.

Define Potential energy

Potential energy can be the energy at rest or energy stored in body. Potential energy may be classified into three groups:

 (1) Due to position – E.g. Water in an elevated reservoir
(2) Due to distortion of an elastic body- E.g. compressed spring
(3) Work through chemical action- E.g. Energy stored in fuel

To calculate potential energy due to position, we use the formula

Potential Energy = Weight × Height (N-m or Joule)

Define kinetic energy.

Kinetic energy is defined as the energy in motion. Running train, flying aircraft and all dynamic objects will posses this energy.

Kinetic Energy = 1⁄2 Mass × Velocity2

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