Statement I If we increase the current sensitivity of a galvanometer by increasing number of turns, its voltage sensitivity also increases. Statement II Resistance of a wire is directly proportional to its length.

Question

Statement I If we increase the current sensitivity of a galvanometer by increasing number of turns, its voltage sensitivity also increases. Statement II Resistance of a wire is directly proportional to its length. (A) Both Statement I and Statement II are correct and Statement II is the correct explanation of Statement I. (B) Both Statement I and Statement II are correct but Statement II is not the correct explanation of Statement I. (C) Statement I is correct but Statement II is incorrect. (D) Statement I is incorrect but Statement II is correct.

Tardigrade Admin · Accepted Answer

Current sensitivity, Si=(N B A/k) and voltage sensitivity, SV=(N B A/k R) So, when Si is increased by increasing number of turns N, length of wire used also increases and so, R increases. Hence, SV may remain same or decrease whereas Si increases.

Q. Statement I If we increase the current sensitivity of a galvanometer by increasing number of turns, its voltage sensitivity also increases.
Statement II Resistance of a wire is directly proportional to its length.

Both Statement I and Statement II are correct and Statement II is the correct explanation of Statement I.

Both Statement I and Statement II are correct but Statement II is not the correct explanation of Statement I.

Statement I is correct but Statement II is incorrect.

Statement I is incorrect but Statement II is correct.

Current sensitivity, $S_{i} = \frac{NB A}{k}$
and voltage sensitivity, $S_{V} = \frac{NB A}{k R}$
So, when $S_{i}$ is increased by increasing number of turns $N$ , length of wire used also increases and so, $R$ increases.
Hence, $S_{V}$ may remain same or decrease whereas $S_{i}$ increases.

Q. Statement I If we increase the current sensitivity of a galvanometer by increasing number of turns, its voltage sensitivity also increases. Statement II Resistance of a wire is directly proportional to its length.