Question

During 3.2 hours of operation, a charge of 72 kC flows through an electric space heater, while the heater generates heat at a rate of 1.5kJ/s. The heater is connected to a constant DC voltage source. Assume that the heating wire inside the heater has a circular cross-section of a 0.5 mm radius and is made of a material with a resistivity of 490 *10^-9m. How long is the wire?

Answer 1