
Efficiency  Electric heater in Al
An electric heater used to heat a 1kg mass of Aluminium (SHC 900J/K/kg)
The meter readings were:
2.51 Amps, 8.49 Volts and the temperature was raised through 6 Kelvin in 450 secs
Efficiency = useful energy out / total energy in
Energy in = I x V x t
Energy out = m x shc x T 
Efficiency  Electric heater in water
A lamp was used to raise the temperature of 50ml (50ml has a mass of 0.05kg) of water (SHC 4200J/K/kg) by 30 Kelvin.
The meter readings were 1.68 Amps, 11.15 Volts and the time taken was 600 secs
Efficiency = useful energy out / total energy in
Energy in = I x V x t
Energy out = m x shc x T 
Efficiency  Electric motor
A geared electric motor used to lift a 1kg mass through a height of 1m.
The meter readings were:
0.23 Amps, 5.97 Volts and the mass was lifted 1m in 29.6 secs
Efficiency = useful energy out / total energy in
Energy in = I x V x t
Energy out = m x g x h
(g = 9.81 N/kg) 
Electrical Energy poster
Simple A3 Electrical Energy poster for Edexcel Topic 9