Physics · 2021
JEE Main · 31 August 2021, Shift 1 · Q10
A coil having N turns is wound tightly in the form of a spiral with inner and outer radii ' a ' and 'b' respectively. Find the magnetic field at…
A coil having N turns is wound tightly in the form of a spiral with inner and outer radii ' a ' and 'b' respectively. Find the magnetic field at centre, when a current I passes through coil :
Official answer
(1)
$\displaystyle \frac{\mu_0 \text { IN }}{2(b-a)} \log _e\left(\frac{b}{a}\right)$
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JEE Main 2021 Physics question, with the answer from NTA’s final answer key. Where our answers come from.