JEE Mains · Physics · STD 12 - 4. Moving charges and magnetism
The electric current in a circular coil of four turns produces a magnetic induction \(32\,T\) at its centre. The coil is unwound and is rewound into a circular coil of single turn, the magnetic induction at the centre of the coil by the same current will be \(..........\,T\)
- A \(8\)
- B \(4\)
- C \(2\)
- D \(16\)
Answer & Solution
Correct Answer
(C) \(2\)
Step-by-step Solution
Detailed explanation
\(B =\frac{\mu_0 i }{2 R } \times 4\) \(B ^{\prime}=\frac{\mu_0 i }{2 R ^{\prime}}\) \(R ^{\prime}=4 R\) \(B ^{\prime}=\frac{\mu_0 i }{8 R }\) \(\frac{ B ^{\prime}}{ B ^{\prime}}=\frac{1}{16}\) \(B ^{\prime}=2\,T\)
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