A ball is dropped from the top of a building. The ball takes 0.5 s to fall past the 3 m length of a window at certain distance from the top of the building.
(g=10m/s2)
How far is the top of the window from the point at which the ball was dropped ?
s=ut+12gt2
3=u(0.5)+12×10(0.5)2
3=(0.5)u+5(0.25)
1.750.5=u
⇒u=3.5 m/s
u2=u21+2gs
(3.5)22g=s
⇒s=3.5×3.52g⇒ s=0.6125 m