Question

Two balls of equal masses are thrown upwards along the same vertical direction at an interval of 2 second ,with same initial velocity of 45 m/s then find at what height balls will collide

Answer 1

t1= 45/10=4.5sec t2=2.5

at instant of 4.5 sec 1st ball lis at Hmax =

and second ball is at

81.25m

so now the distance bw them is 60m

and they are under gravity so

grelative=

v at that instant =u-gt=45-25=20m/s

h(distance between balls)= u(ball b with respect to ball a)*t

60=(ub+ua)*t

60=(20+0)+t

t=3sec

H=1/2g3²

H= 45 m