A heater operated from a 250 V, 50 Hz single phase supply consumes 2.5 kWh in one hour. If it is now connected to a square wave generator of 400 V peak to peak voltage and frequency 150 Hz the power dissipated by the heater will be:
1
5 kW
2
2.8 kW
3
3.2 kW
4
6.4 kW
5
1.6 kW