JEE Mains · Physics · STD 11 - 3.2 motion in plane
The stream of a river is flowing with a speed of \(2\,km/h.\) A swimmer can swim at a speed of \(4\,km/h.\) ....... \(^o\) should be the direction of the swimmer with respect to the flow of the river to cross the river straight .
- A \(60\)
- B \(90\)
- C \(120\)
- D \(150\)
Answer & Solution
Correct Answer
(C) \(120\)
Step-by-step Solution
Detailed explanation
\begin{array}{l} For\,swimmer\,to\,cross\,the\,river\,straight\\ \Rightarrow \,\,\,\,\,4\,\sin \,\theta = 2\\ \Rightarrow \,\,\,\,\,\sin \,\theta \, = \frac{1}{2}\, \Rightarrow \,\theta \, = {30^ \circ }\\ So,\,angle\,with\,direction\,of\,river\,flow\,\\ = {90^ \circ } + \theta…
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