Question
Physics Question on Motion in a plane
The width of river is 1 km. The velocity of boat is 5 km/hr. The boat covered the width of river in shortest time 15 min. Then the velocity of river stream is
A
3 km / hr
B
4 km / hr
C
29 km / hr
D
41 km / hr
Answer
3 km / hr
Explanation
Solution
vResultant=1/4hr1km=4km/hr
∴vRiver=52−42=3 km /hr.
So, the correct answer is (A): 3 km / hr.