Physics-
General
Easy
Question
A boat takes two hours to travel 8 km and back in still water. If the velocity of water 4 
, the time taken for going ups tream 8km and coming back is
- 2h
- 2 h 40 min
- 1 h 20 min
- Cannot be estimated with the information given
The correct answer is: 2 h 40 min
Boat covers distance of 16 km in a still water in hours
8
Now, velocity of water
Time taken for going upstream
h
(As water current oppose the motion of boat) Time taken for going downstream
h
(As water current helps the motion of boat)
Total time 
h=2 h 40 min
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