ELECTROMAGENTISM

 

                             Electromagnetic induction – pal -revision day 2

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Answers

1, A 2, A 3, B 4, D 5, C 

6, current flows through the solenoid which behaves like a magnet. The armature is pulled by the electromagnet which hits the gong. The armature loses contact and there by open the circuit. The soft iron loses magnetism and the armature is returned. The bell rings continuously as this process is repeated.

There will be no change and the bell rings as before.

7

The magnetic field through the solenoid increases that induces emf in the solenoid and as a result current flow through it. When the magnet leaves the solenoid, once again magnetic flux changes and induces emf but in the opposite direction.

 

 

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