JEE Mains · Physics · STD 11 - 3.2 motion in plane
A river of width 200 m is flowing from west to east with a speed of \(18 km / h\). A boat, moving with speed of \(36 km / h\) in still water, is made to travel one-round trip (bank to bank of the river). Minimum time taken by the boat for this journey and also the displacement along the river bank are _________ and _________ respectively.
- A 20 s and 100 m
- B 40 s and 0 m
- C 40 s and 200 m
- D 40 s and 100 m
Answer & Solution
Correct Answer
(C) 40 s and 200 m
Step-by-step Solution
Detailed explanation
Minimum time : \(t _{\min }=\frac{200}{10}=20 sec\) \(t_{\min }=\frac{200}{10}=20 sec\) For round trip \(=40 sec\). Displacement along river bank \(=40 \times 5=200 m\)
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