Changes in energy

• Energy changes can be calculated for a moving object , a stretched spring and an object raised above the ground.
• Kinetic energy is stored in moving objects and is calculated by:

  Kinetic energy ( J ) = 1/2 X mass ( kg ) X speed² ( m/s )²
• Kinetic energy is directly proportional to the mass of the moving object: doubling the mass doubles the kinetic energy of the moving object.
• Kinetic energy is directly proportional to the ² of speed so doubling the speed means that kinetic energy increases by a factor of 4
• The amount of gravitational potential energy gained by an object raised above the ground is calculated by using the equation:

  gravitational potential energy ( J ) = Mass ( kg ) X gravitational field strength ( N/Kg) x height ( m )