Question

Ram is a student of class X in a village school. His uncle gifted him a bicycle with a dynomo ditted in it. He was very excited to get it. While cyciling during night, he could light the bulb and see the object on the teacher considered it an opportunity to explain the working to the whole class.

Answer 1

(i) Principle. When amount of manetic flux linked with a coil changes, an e.m.f. is induced in the coil. The due to e.m.f. lasts so long as change in magneitc flux continues. The bulb fitted in the cynamo lights due to e.m.f. induced in the coil of dynomo. The bulb stops glowing when the cycle stops.
(ii) Ram showed the spirit of learning. He also throught how his classmates could benefit alongwith him. The leader teacher discharged his responsibility of explaining things to the entire class, encouraging them to learn new things.