A ball rolls off the top of stairway with a horizontal velocity of magnitude 1.8 ~m / s . The steps are 0.20 m high and 0.20 m wide. Which step will the ball hit first?

Step-by-step solution

Given, x=0.20 ~m , y=0.20 ~m , u=1.8 ~m / s Let the ball strikes the n th step of stairs, Vertical distance travelled =n y=n 0.20= 1 2 g t^2 Horizontal distance travelled, n x=u t or t= n x u n y= 1 2 g n^2 x^2 u^2 or n= 2 u^2 g y x^2 = 2 (1.8)^2 0.20 9.8 (0.20)^2 =3.3 4