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The rowing speed of a man relative to wa...

The rowing speed of a man relative to water is `5 kmh^(-1)` and the speed of water flow is `3 kmh^(-1)`. At angle to the river flow should he head if he wants to reach a point on the other bank, directly opposite to starting point ?

A

`127^(@)`

B

`143^(@)`

C

`120^(@)`

D

`150^(@)`

Text Solution

Verified by Experts

The correct Answer is:
A
`sin theta = (upsilon_(r ))/(upsilon_(br))=(3)/(5)`

`therefore theta = 37^(@)`
The required angle is therefore
`90^(@)+theta=90^(@)+37^(@)=127^(@)`
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Knowledge Check

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