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:

Options

A. `0*001`
B. `0*01`
C. `1`
D. `0*05`

Explanation

To solve the problem of converting a milli-voltmeter with a range of 25 millivolts into an ammeter with a range of 25 amperes, we need to calculate the value of the necessary shunt resistor. Here’s a step-by-step solution:

### Step 1: Understand the given values
- The milli-voltmeter has a full-scale deflection (FSD) voltage, \( V = 25 \, \text{mV} = 25 \times 10^{-3} \, \text{V} \).
- The desired current range for the ammeter is \( I = 25 \, \text{A} \).

### Step 2: Calculate the current through the galvanometer
The current through the galvanometer, \( I_g \), can be calculated using Ohm's law, where \( V = I_g \times G \) (G is the resistance of the galvanometer). Rearranging gives:
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