A steamer is moving due cast with 36 km/h. To a man in the stearer the wind appears to blow at 18 km/h de north. Find the velocity of the wind.

Options

A. `5sqrt(5)^(-1) tan^(-1)` north of east
B. `5 ms^(-1) tan ^(-1)(2)` North of East
C. `5sqrt(5) ms^(-1) tan^(-1) (2)` North of East
D. `5 ms^(-1) tan^(-1) (1/2)` North of East

Answer

A

Explanation

`v_(ws)=v_(w)-v_(s) rarr (v_(wx)hati+v_(wy)hatj)-10hati-5hatj)`
`|v_(w)|=5sqrt(5)` and `theta = tan^(-1) (1/2)` ie, wind is blowing at `5sqrt(5) ms^(-1)` ms velocity, at an angle tan North of East