WBJEE · Physics · Current Electricity
The magnets of two suspended coll galvanometers are of the same strength so that they produce identical uniform magnetic fields in the region of the coils. The coil of the first one is in the shape of a square of side a and that of the second one is circular of radius \(\frac{a}{\sqrt{\pi}},\) When the same current is passed through the coils, the ratio of the torque experienced by the first coil to that experienced by the second one is
- A \(1: \frac{1}{\sqrt{\pi}}\)
- B 1: 1
- C \(\pi: 1\)
- D \(1: \pi\)
Answer & Solution
Correct Answer
(B) 1: 1
Step-by-step Solution
Detailed explanation
In galvanometer \(I \sim \theta=G \theta\) Where, \(\quad G=\frac{k}{N A B}\) When coil is in square of shape, \[ G=\frac{k}{N A B}=\frac{k}{N a^{2} B} \] When coil is in circular shape of radius \(a / \sqrt{\pi}\)…
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