Question

Prove that when a body thrown vertically upward its time of ascent is equal to descent.

Answer 1

let the velocity at the time of throwing be Uthus the time for the velocity to become 0 at the highest point of flight.Thus by first equation of motion thus t1 = U/gHeight attained, H = U2/2g          uisng the second equation of motionNow at the time the time of descent,time taken for the ball to come down will be:t22 = 2H/g            using the third equation of motionthus t2 = (U/g)2 clearly t1 = t2