Current Electricity Charging Discharging Of Capacitors Question 185
Question: A moving coil galvanometer has 150 equal divisions. Its current sensitivity is 10 divisions per milliampere and voltage sensitivity is 2 divisions per millivolt. In order that each division reads 1 volt, the resistance in ohms needed to be connected in series with the coil will be
[AIEEE 2005]
Options:
A) 99995
B) 9995
C) $ 10^{3} $
D) $ 10^{5} $
Show Answer
Answer:
Correct Answer: B
Solution:
Voltage sensitivity $ =\frac{\text{Current sensitivity}}{\text{Resistance of galvanometer},\text{G}} $
Therefore $ G=\frac{10}{2}=5,\Omega $ . Here $ i _{g}= $ Full scale deflection current $ =\frac{150}{10}=15,mA $ . V = Voltage to be measured = 150 ´ 1 = 150 V. Hence $ R=\frac{V}{i _{g}}-G=\frac{150}{15\times {{10}^{-3}}}-5=9995,\Omega $ .
BETA
