The current sensitivity of a moving coil galvanometer increases by `20%` when its resistance is increased by a factor 2. Calculate by what factor does the voltage sensitivity change?

Explanation

To solve the problem step by step, we need to understand the relationship between current sensitivity, voltage sensitivity, and resistance in a moving coil galvanometer.

### Step-by-Step Solution:

1. **Understanding Current Sensitivity**:
The current sensitivity (S) of a moving coil galvanometer is given by the formula:
\[
S = \frac{\Phi}{I} = \frac{nAB}{C}
...