Question

A battery is made up of 8 cells in series. Each cell has an e.m.f. of 1.5 V.

The battery is connected to one 8.0 Ω resistor for 40 minutes.

(a) Calculate the e.m.f. of the battery. (1 mark)


(b) Calculate the energy transferred from the battery in 40 minutes.
(4 marks)

Answer 1

Answer:

1. Total e.m.f. of the battery = 1.5*8 = 12 V

2. P = VI = V^2/R

= 12*12/8 = 12*3/2 = 18 W

Energy transferred

E = P*t = 18*40*60 = 43200

E = 4.32 kJ