JEE Mains · Physics · STD 12 - Moving charges and magnetism
- JEE Mains 2023
- Easy
- Numerical
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 \(..........\,T\)
Pick an option to check your answer.
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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