The number of turns of the coil of a moving coil galvanometer is increased in order to increase current sensitivity by $50 \%$ The percentage change in voltage sensitivity of the galvanometer will be:
The number of turns of the coil of a moving coil galvanometer is increased in order to increase current sensitivity by $50 \%$ The percentage change in voltage sensitivity of the galvanometer will be:
Show Hint
- $50 \%$
- $75 \%$
- $0 \%$
- $100 \%$
The Correct Option is C
Solution and Explanation
The voltage sensitivity \( V_s \) of a moving coil galvanometer is inversely proportional to the number of turns of the coil. Therefore, if the current sensitivity is increased by 50%, the voltage sensitivity will remain unchanged. Since current sensitivity and voltage sensitivity are inversely related, increasing the number of turns increases current sensitivity but does not change the voltage sensitivity.
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Concepts Used:
Torque
Torque is a moment of force. Torque is measured as a force that causeque is also defined as the turning effect of force on the axis of rotation. Torque is chs an object to rotate about an axis and is responsible for the angular acceleration. Characterized with “T”.
How is Torque Calculated?
Torque is calculated as the magnitude of the torque vector T for a torque produced by a given force F
T = F. Sin (θ)
Where,
r - length of the moment arm,
θ - the angle between the force vector and the moment arm.
Read More: Torque
Types of Torque
Torque is of two types:
- Static torque
- Dynamic torque