Tue March 08, 2011 By: Arunima Iyer

A motor boat going downstream overcame a raft at a point A, t=60 minutes later it turned back and after sometime the motor boat passed the raft at the distance 6km from the point A.Find the flow velocity of stream assuming velocity of motor boat with respect to stream is constant throughout.

Expert Reply
Tue March 08, 2011
If the motorboat moves with constant velocity, then the distance the boat travels from the raft,

d = v*t

The time to travel back then is same d, same v so ... same t.

t + t = 2 t

Distance the river traveled in 2 t is 6 km.

6 km /2 t = 6 km / 2 hr = 3 km/hr.
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