Question

A river is flowing with a speed of $1km/h$. A swimmer wants to go to point C starting from A. He swims with a speed of $5km/h$ at an angle $\theta$ w.r.t the river. IF $AB=BC=400m$. Then the value of $\theta$ is

• A. ${37}^o$
• B. ${30}^o$
• C. ${53}^o$
• D. ${45}^o$

Answer 1

The correct option is D ${45}^o$

$\tan (90°-\theta )=\frac{BC}{AB}=1$

$90°-\theta =45°$

$\theta =45°$