Question

In a restaurant, WiFi signal has to be provided only to the deluxe class. Signal reaches each of the customer upto a distance of 21 m from the antenna and the total area for which signal to be provided is 231 $m^2$. What is the angle (in degrees) at which the signal has to be spread over a sector by the antenna?

• A. 60
• B. 90
• C. 45
• D. 180

Answer 1

The correct option is A

60

Given , Radius r = 21 m .

Area of sector = $\frac{\theta }{360}$ × $\pi \times r^2$

⇒ 231 = $\frac{\pi \times {21}^2\times \theta }{360}$

$\theta$ = ${60}^{\circ }$