JEE Mains · Physics · STD 12 - 4. Moving charges and magnetism
The current sensitivity of a galvanometer can be increased by: \((A)\) decreasing the number of turns \((B)\) increasing the magnetic field \((C)\) decreasing the area of the coil \((D)\) decreasing the torsional constant of the spring Choose the most appropriate answer from the options given below.
- A \((B)\) and \((C)\) only
- B \((C)\) and \((D)\) only
- C \((A)\) and \((C)\) only
- D \((B)\) and \((D)\) only
Answer & Solution
Correct Answer
(D) \((B)\) and \((D)\) only
Step-by-step Solution
Detailed explanation
\(i=\left(\frac{ K }{ NAB }\right) \theta\) \(\therefore \frac{ d \theta}{ di }=\frac{ NAB }{ K }\)
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