Question

If the number of turns is increased in any moving coil galvanometer, then its sensitivity

• A. increases
• B. decreases
• C. remains unchanged
• D. may increase or may decrease

Hint:

In a moving coil galvanometer, increasing the number of turns results in increased sensitivity due to stronger induced magnetic fields.

Answer 1

The Correct Option is A

Step 1: Sensitivity of a galvanometer.
The sensitivity of a moving coil galvanometer is given by \( S = \frac{N}{I} \), where \( N \) is the number of turns, and \( I \) is the current.
Step 2: Increasing number of turns.
When the number of turns (\( N \)) increases, the coil generates a stronger magnetic field, which increases the deflection for the same current. Hence, the sensitivity increases.
Step 3: Elimination.
- (A) increases: Correct, as sensitivity is directly proportional to the number of turns.
- (B) decreases: Incorrect, sensitivity increases with more turns.
- (C) remains unchanged: Incorrect, as increasing turns does affect sensitivity.
- (D) may increase or may decrease: Incorrect, it always increases.
Step 4: Conclusion.
Thus, increasing the number of turns in a galvanometer increases its sensitivity.