Question : A ball is dropped from top of a building. The ball take 0.5 s to fall past the 3 m length of window some distance from top of building with what speed does the ball pass the top of window?
(A) 6ms^{-1}
(B) 12ms^{-1}
(C) 7ms^{-1}
(D) 3.5ms^{-1}
Answer :
Solution :

