Question

The number of turns of the coil of a moving coil galvanometer is increased in order to increase current sensitivity by 50%. The percentage change in voltage sensitivity of the galvanometer will be 

(1) 100% 

(2) 50% 

(3) 75% 

(4) 0%

Answer 1

Correct option is (4) 0%

Current sensitivity = Voltage sensitivity × R 

Current sensitivity is made 1.5 times. 

R also increase 1.5 times.

Hence voltage sensitivity = 1.5 current sensitivity / 1.5 x R = no change.