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Assertion (A): On Increasing the current sensitivity of a galvanometer by increasing the number of turns may not necessarily increase its voltage sensitivity.

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Question

Assertion (A): On Increasing the current sensitivity of a galvanometer by increasing the number of turns may not necessarily increase its voltage sensitivity.

Reason (R): The resistance of the coil of the galvanometer increases on increasing the number of turns.

Select the most appropriate answer from the options given below:

Options

  • Both A and R are true and R is the correct explanation of A.

  • Both A and R are true but R is not the correct explanation of A.

  • A is true but R is false.

  • A is false and R is also false.

MCQ
Assertion and Reasoning
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Solution

Both A and R are true and R is the correct explanation of A.

Explanation:

When the number of turns in a coil is increased, the resistance of the coil increases as well. As a result, higher current sensitivity does not always equal increased voltage sensitivity.
`"V"_"g" = "l"_"g"/"R"`
∴ if Ig ↑ & R ↑ by different amounts, then Vg may increase or decrease.
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