In the above circuit, the inductor is connected to a battery through a switch. In that when the switch is closed, the current will induce in the circuit. The magnetic flux will be increased. Change in flux will induce emf. When the switch has opened the drop in the current occur is more than the increase in the current when the switch is closed.

Due to this large amount of emf is induced in the inductor when the switch is closed as compared to when the switch is opened.