Question

Wind is blowing $NE$ with $18\sqrt{2}km/h$ and steamer is heading due west with $18km/h$. In which direction is the flag on the mast fluttering?

• A. North West
• B. North
• C. South West
• D. South

Answer 1

The correct option is D South

Flag blows in the direction opposite to resultant velocity of steamer and wind.
Resultant velocity, $V_{Resultant}=-18\hat{i}+18\sqrt{2}cos\left({45}^o\right)\hat{j}+18\sqrt{2}sin\left({45}^o\right)\hat{i}=18\hat{j}$
Thus flag flutters in $-\overrightarrow{j}$ or South direction