Consider the circuit in the figure.

(a) how much energy is absorbed by electrons from the initial state of no current (ignore thermal motion) to the state of drift velocity?
(b) Electrons give up energy at the rate of `Rl^(2)` per second to the thermal energy. What time scale would the number associate with energy in problem (a)? n = number of electron/volume `=10^(29)//m^(3)`. Length of circuit = 10cm cross-section = `A = (1mm)^(2)`.

Answer

A