posted by louis aaaa on .
A woman on a bridge 81.6 m high sees a raft floating at a constant speed on the river below. She drops a stone from rest in an attempt to hit the raft. The stone is released when the raft has 9.13 m more to travel before passing under the bridge. The stone hits the water 4.30 m in front of the raft. Find the speed of the raft.
The stone takes 4.08 sec to hit the water.
The boat moved 9.13-4.30=4.83m in 4.08s
So, its speed is 1.18 m/s