NEET Solved Paper 2019 Question 6

Question: The speed of a swimmer in still water is 20 m/s. The speed of river water is 10 m/s and is flowing due east. If he is standing on the south bank and wishes to cross the river along the shortest path, the angle at which he should make his strokes w.r.t. north is given by: [NEET 5-5-2019]

Options:

A) $ 60{}^\circ $ west

B) $ 45{}^\circ $ west

C) $ 30{}^\circ $ west

D) $ 0{}^\circ $

Show Answer

Answer:

Correct Answer: C

Solution:

  • $ V _{m}\sin \theta =V _{r} $ $ 20\sin \theta =10 $ $ \sin \theta =1/2 $ $ \theta =30{}^\circ $ So $ 30{}^\circ $ west with respect to north