A man lifts a luggage of 25 kg from the ground and puts it on the head, 2.5 m above the ground. If the value of g = 10 m/s2, then the value of work done by him on the luggage is
A source maintains a current I in a resistor of resistor of resistance R. If V is the potential difference across the resistor. The electrical energy dissipated in the resistor in time is given _____