A ball is dropped from the top of a building 100 ~m high. At the same instant another ball is thrown upwards with a velocity of 40 ~m / s from the bottom of the building. The two balls will meet after

Step-by-step solution

Let balls meet after t ~s . The distance travelled by the ball coming down is s₁= 1 2 g t^2 Distance travelled by the other ball array ll & s₂=40 t- 1 2 g t^2 & s₁+s₂=100 ~m & 1 2 g t^2+40 t- 1 2 g t^2=100 ~m & t= 100 40 =2.5 ~s array