Question

cares a maximum current of 50 ampere when a voltage of and 75 milli volt is applied to it how to convert this into a voltmeter to read upto 150 volt and into a ammeter to read upto 25 ampere ​

Answer 1

Explanation:

by connecting a shunt resistance it can be converted into an ammeter.

ammeter range=25A

let shunt resistance be R.

so voltage across parallel circuit is same,

circuit current=25A

25×75×10power-3/50=(50-25)×R

R=1.5 milli ohms

to convert it into a voltmeter a series resistance R2 is required.

as the current through series circuit is same.

so. 150/(75×10power-3)÷50=(75×10power-3)/R

R=75 micro ohms