A motor is connected to a power supply which supplies 6 amperes of current with a 20-volt potential difference. The motor is used to lift a mass which is 40 kg. The motor has a 10% efficiency rating.
The power provided by a power supply is given by
P = IΔV
where P is power in Watts, I is current in amperes, and ΔV is the potential difference in volts. (Use g = 10 m/s2.)
If the motor is run for 60 seconds, how high does the mass rise?