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Current sensitivity of a moving coil gal...

Current sensitivity of a moving coil galvanometer is 5 div/mA and its voltage sensitivity (angular deflection per unit voltage applied) is 20 div/V. The resistance of the galvanometer is

A

`500Omega`

B

`40Omega`

C

`250Omega`

D

`25Omega`

Text Solution

Verified by Experts

The correct Answer is:
C
`theta/I=5/10^(-3)("div")/Aandtheta/V=20("div")/V`
but `theta/V=(NAB)/(KR)" "(becausetheta/I=(NAB)/K)`
`thereforetheta/V=theta/(IR)" "therefore5000xx1/20=250" "thereforeR=250Omega`
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