Question

A cell has an emf of 6V, internal resistance of 1 ohms and a current of 0.5 A passing through it. This cell is connected to a resistor. Find out the resistance of the resistor.

(a) 10 ohms

(b) 11 ohms

(c) 12 ohms

(d) 13 ohms

This question was posed to me during an online exam.

My doubt is from Current Electricity in chapter Current Electricity of Physics – Class 12

Answer 1

The correct choice is (b) 11 ohms

The explanation is: Emf (e) = 6V; Internal resistance (r) = 1 ohms; Current (I) = 0.5A

Required equation: I = \(\frac {e}{R}\) + r

0.5 = \(\frac {6}{R}\) + 1

R = \(\frac {(6 – 0.5)}{0.5}\)

R = 11 ohms

Therefore, the resistance of the resistor is 11 ohms.