Question

Given below are some devices. Identify the one that does not work on the principle of electromagnetic induction. Also mention the principle on which it works.
(a) Dynamo
(b) Loud speaker
(c) Microphone
(d) Transformer

Answer 1

(a) Dynamo : Dynamos produce electric current by rotating a wire within a magnetic field which is based on the working principle of electromagnetic induction.

(b) : Loud speaker : It is based on the principle of motor

(c) Microphone : It is also based on the principle of electromagnetic induction.

(d) : Transformer: Transformer is based on the principle of electromagnetic induction in which induced emf plays an important role.