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A river is flowing towards with a veloci...

A river is flowing towards with a velocity of `5 m s^-1`. The boat velocity is `10 ms^-1`. The boat crosses the river by shortest path. Hence,

A

The direction of boat's velocity is `30^@` west of north.

B

The direction of boat's velocity is north - west.

C

Resultant velocity is `5 ms^-1`.

D

Resultant velocity of boat is `5 sqrt(2) m s^-1`.

Text Solution

Verified by Experts

The correct Answer is:
A
(a.,c.) For angle `theta` in west of north,
`sin theta = (5)/(10) = 0.5`, i.e., `theta = 30^@`
`V_r` = resultant velocity
=`sqrt((10^2) - (5)^2) = 5 sqrt(3) ms^-1`
So, option (a) and (c ) are correct.
.
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