The speed of a boat is 5 km/h in still water. It crosses a river of width 1 km along the shortest possible path in 15 minutes. The velocity of the river water is [IIT 1988; CBSE PMT 1998, 2000]
A) 1 km/h B) 3 km/h C) 4 km/h D) 5 km/h
Answers
Answered by
4
let speed of water be x km\hr
net speed of boat is 5-x km\hr
given time is 1\4hr
since shortest distance is 1km i.e.,width
so [5-x]×1\4=1. [speed ×time=distance]
=5-x=4
x=1km\hr
net speed of boat is 5-x km\hr
given time is 1\4hr
since shortest distance is 1km i.e.,width
so [5-x]×1\4=1. [speed ×time=distance]
=5-x=4
x=1km\hr
Similar questions