Question

The length of a string between a kite and a point on the ground is 90m. The string makes an angle of ${60}^{\circ }$ with the level ground if there is no slack in the string, the height of the kite is

• A. $90\sqrt{3}m$
• B. $45\sqrt{3}m$
• C. $180m$
• D. $45m$

Answer 1

The correct option is B $45\sqrt{3}m$

Let $A$ be the kite and $AC$ is $90$m

In $\Delta ABC$

$\sin {60}^0=\frac{AB}{AC}$

$=\frac{h}{90}$

$\therefore \frac{\sqrt{3}}{2}=\frac{h}{90}$

$\therefore h=45\sqrt{3}$m