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Choose the correct option.
A circular coil has radius 'r', number of turns 'N' and carries a current 'I'. Magnetic flux…
A circular coil has radius '$r$', number of turns '$N$' and carries a current '$I$'. Magnetic flux density '$B$' at its centre is:
- (a)$B = \mu_0 NI$
- (b)$B = \mu_0 NI / 2r$
- (c)$B = \mu_0 NI / 4\pi r$
- (d)$B = \mu_0 NI / 4r$
Answer
Answer
Correct option: (b)
Answer: (b) $B = \mu_0 NI / 2r$
The field at the centre of a circular coil of $N$ turns is $B = \mu_0 NI/2r$.