A 10Ω resistor is connected first to a 220V d.c. source and then to a 220V (r.m.s.) a.c. mains supply for the same time interval of 2min.
a. (i) Calculate the heat produced in the resistor when it is connected to the d.c. source.
b. (ii) Calculate the heat produced when the same resistor is connected to the 220V (r.m.s.) a.c. mains for the same time interval.
c. (iii) Compare the two values obtained and state your conclusion with reason.