A wheel with 8 matallic spokes each 50 cm long is rotated with a speed of 120 `rev//min` in a plane normal to horizontal component of earth's magnetic field. Earth's magnetic field at the phase is 0.4 G and angle of dip `60^(@)`. Calculate the emf induced between the axle and rim of the wheel. How is the emf affected if number of spokes is increased ?

Explanation

To solve the problem, we will follow these steps:

### Step 1: Convert the rotational speed from revolutions per minute (rpm) to radians per second (rad/s).
Given:
- Speed of rotation = 120 revolutions/minute

To convert this to rad/s:
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