Question

Two towers(the towers are the same) are built next to each other. the distance between them is d and there height is 10,000d. a ball is thrown horizontally from one tower to the other with spped v=sqrt(gd/2). assuming the ball collied elasticlly with the wall, therfore his speed parallel to the wall is the same and the speed perpendicular to the wall switches direction after each collison. how many times will the ball colide before reaching the floor?
1)10
2)100
3)1,000
4)10,000
5)20
6)200
7)2,000
8)20,000
9)You cant know for certain.

I assumed the answer is 8)- 20,000. is it correct? (if not so i probabley understood the question wrong so please guide me in the right direction)

Answer 1

I was wrong i meant, 6)- 200