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Given below are two statements: Statement I: If the number of turns in the coil of a moving coil galvanometer is doubled then the current sensitivity becomes double. Statement II: Increasing current sensitivity of a moving coil galvanometer by only increasing the number of turns in the coil will also increase its voltage sensitivity in the same ratio. In the light of the above statements, choose the correct answer from the options given below:
- Statement I is true but Statement II is false
- Statement I is false but Statement II is true
- Both Statement I and Statement II are false
- Both Statement I and Statement II are true
Correct answer: Statement I is true but Statement II is false
Solution
Statement I is correct because doubling the number of turns in the coil increases the magnetic field interaction, thereby doubling the current sensitivity. However, Statement II is false because while current sensitivity increases with more turns, voltage sensitivity is influenced by other factors such as the resistance of the coil, and does not necessarily increase in the same ratio.
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