The deflection in a moving coil galvanometer falls from 50 divisions to 10 divisions when a shunt of 12 ohm is applied. What is the resistance of the galvanometer?

Explanation

To solve the problem, we need to find the resistance of the galvanometer (Rg) given the change in deflection when a shunt resistance (Rs) is applied. Here’s a step-by-step solution:

### Step 1: Understand the relationship between current and deflection
The deflection in a galvanometer is proportional to the current passing through it. Let:
- \( I \) be the current through the galvanometer when the deflection is 50 divisions.
- \( I' \) be the current through the galvanometer when the deflection is 10 divisions.

From the problem, we can express these currents as:
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