Physics

Problem

A moving-coil galvanometer has a resistance of

50\,\Omega

and requires a current of

2.0\,\text{mA}

for full-scale deflection. a. (a) Determine its current sensitivity in

\text{rad A}^{-1}

if the restoring constant of the suspension is

2.0\times10^{-6}\,\text{N m rad}^{-1}

and the effective factor

NAB

equals

5.0\times10^{-5}\,\text{m}^2\text{T}

. b. (b) The galvanometer is to be converted into an ammeter that reads up to

5.0\,\text{A}

. Calculate the value of the shunt resistance required (assume the galvanometer resistance remains unchanged).