Equations

• Work done (J)= Force applied, f (N) x Distance, s (M)
• Change in objects gravitational potential energy store (J)= mass, m (kg) x gravitational field strength (N/kg) x height (m)
• • Kinetic energy, Ek= 1/2 x mass, m (kg) x speed^2, v^2 (m/s)^2
• Elastic potential energy, Ee (J)=1/2 x spring constant, k (N/m) x extension^2, e^2 (m)^2
• Efficiency (%)= Useful output energy transferred by the device (J)/ Total input energy supplied to the device (J) x 100%
• Power, P (Watts, W)= Energy transferred to the appliance, E (J)/ Time taken for the energy to be transferred, t (seconds)
• Power wasted= Total power in- Useful power out
• Energy= Power x time