A circular coil having 500 turns and resistance 4 `Omrga` placed in a horizontal component of Earth's magnetic field of `4 xx 10^(-5) T` induces an emf of 0.004 volt when rotated about its vertical diameter through `180^(@)` in 0.15 s. Calculate the radius of the coil. Also find the induced current in the coil.

Explanation

To solve the problem step by step, we will break it down into manageable parts.

### Given Data:
- Number of turns in the coil, \( N = 500 \)
- Resistance of the coil, \( R = 4 \, \Omega \)
- Horizontal component of Earth's magnetic field, \( B = 4 \times 10^{-5} \, T \)
- Induced emf, \( E = 0.004 \, V \)
- Angle of rotation, \( \theta = 180^\circ \)
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