Solve the following question given below:
Question I: How much current is drawn by a 100 W light bulb operating in a 240 V circuit (assume DC)?
Question II: If the current is given by I = nevdA , where n is the number of free electrons per unit volume and A the cross sectional area of the wire, calculate vd in a copper wire of A = 0.5 mm2 . And n = 8.5 x 1028 m-3.
Question III: Considering your answer to part (b), explain why a light comes on almost instantaneously when switched on from a switch several meters away.
Please explain your answer. I know substitution is involved so be sure to give a detailed explanation on that as well.