Question

A swimmer reaches the other bank of a flowing
river exactly opposite to the starting point. If he was
swimming at 2 km/hr while maintaining 150° with
the flow, then time taken by him to cross the river
1 km wide is​

Answer 1

Answer:

good question

Explanation:

may hope you understand I have applied direct formulas

Answer 2

Answer:1 hr

Explanation:

Given

velocity of swimmer with respect to flow is 2 km/h

maintaining  an angle of $150 ^{\circ}$ with horizontal

its velocity is divided in to cos and sin component

Only sin component will help to cross the river

velocity sin component is $2\sin 150=2\cos 60=1 km/h$

and width of river is 1 km

thus time taken is $=\frac{1}{1}= 1 hr$