Question

A milli voltmeter of $25$ milli volt range is to be converted into an ammeter of $25$ ampere range. The value (in ohm) of necessary shunt will be

• A. 0.001
• B. 0.01
• C. 1
• D. 0.05

Answer 1

Answer: (A)

0.001

Answer 2

If the resistance of the meter is $G$ then the full scale deflection current
$i _{ g }= \frac{25 mV }{ G }$ ampere
The Value of shunt required for converting it into ammeter of range $25$ ampere is
$S =\frac{ i _{ g } G }{ i - i _{ g }}$
So $\approx \frac{25 mV }{25}=0.001\, \Omega$