A car runs at a constant speed on a circular track of radius 100 m, taking 62.8 seconds for every circular lap. The average velocity and average speed for each circular lap respectively is

Two bodies A (of mass 1 kg) and B (of mass 3 kg) are dropped from heights of 16 m and 25 m, respectively. The ratio of the time taken by them to reach the ground is

The displacement x of a particle varies with time t as x = ae^$$-$$at + be^{$$\beta $$t}, where a, b, $$\alpha $$ and $$\beta $$ are positive constants. The velocity of the particle will

A ball is thrown vertically upward. It has a speed of 10 m/sec when it has reached one half of its maximum height. How high does the ball rise?
(Take g = 10 m/s².)