A body of mass 2 kg is thrown up vertically with K.E of 490 joules If the acceleration due to gravity is 9.8 m/s2 the height at which the K.E of the body becomes half its original value is give by:
A train of 150 m length is going towards north direction at a speed of 10 ms-1. A parrot flies at a speed of 5 ms-1towards south direction parallel to the railway track. The time taken by the parrot to cross the train is equal to
The primary winding of transformer has 500 turns whereas its secondary has 5000 turns. The primary is connected to an a.c. supply of 20 V, 50 Hz. The secondary will have an output of