Discuss Faraday's experiment which shows that relative motion is not an absolute requirement for electromagnetic induction.

Explanation

Figure shows two coils `C_1` and `C_2` held stationary. Coil `C_1` is connected to galvanometer G while the second coil `C_2` is connected to a battery through a tapping key K.
It is observed that the galvanometer shows a momentary deflection when the tapping key K is pressed. The pointer in the galvanometer returns to zero immediately. If the key is held pressed continuously, there is no deflection in the galvanometer.

When the key is released, momentary deflection is observed again, but in the opposite direction. It is also observed that the deflection increases dramatically when an iron rod is inserted into the coils along their axis.
Conclusion : Relative motion is not an absolute requirement to induce current.