Which one of the following statement is wrong ?

Options

A. Radio horizon of the transmitting antenna for space wave is `d_T=sqrt(2 Rh)` , where R is the radius of the earth and h is the height of the transmitting antenna .
B. Within the skip distance neither the ground waves nor the sky waves are received
C. Radiowaves in the frequency range 30 MHz to 60 MHz are called sky waves
D. For the propagation of ground waves horizontal aerials are used

Answer

C

Explanation

For sky waves the frequencies are between 3 MHz and 30 MHz is a correct statement ( c) is wrong.