Question

An antenna of length 25 m is mounted on top of a building of height 75 m. Then the maximum wavelength of the transmission signal is close to :

(1) 100 m          (2) 200 m         (3) 300 m         (4) 400 m

Answer 1

The correct option is 1)100 m 

Length of antenna $\ge \frac{\lambda }{4}$ 

$\lambda \le 4\times 25$ 

$\lambda \le 100m$