Make an AC generator using a magnet and a coil
Make the connections to the solenoid as shown in the figure.
Now rotate a magnet on the plane containing its magnetic axis, and bring the solenoid close to it such that its axis is also parallel to this plane. Use the picture shown as a reference.
Observe the plot of the induced EMF, and calculate its time period. This time period should correspond to the RPM of the magnet.
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