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a) The figure below shows a motor connected to a magnetic switch called a relay operated by an ordinary S switch S1. Use the information in the figure to answer questions that follow.

i).Explain how the relay switches on the motor when S1 is closed.
ii) State with a reason the effect on the motor if the iron core is replaced with a steel core and switch S1 is put on and then off.

Answer Text:
i).When S1 is closed soft iron core is magnetized and attract soft iron armature. The insulator pushes the spring to make contact switching on the motor.
ii) The motor continues running
Reason
The steel core retains magnetism for a longer time.