In short wave communication, waves of which of the following frequenci

1.	In short wave communication, waves of which of the following frequencies will be reflected back by the ionospheric layer having electron density 1011 m-3?(a) 2 MHz (b) 10 MHz (c) 12 MHz (d) 18 MHz
Answer» (a) 2 MHz Critical frequency, f_c = 9 (N_max)^1/2 = 9(10¹¹)^1/2 = 2.8 x 10⁶ Hz = 2.8 MHz ∴ The wave of frequency 2 MHz will be reflected by the ionosphere.

In short wave communication, waves of which of the following frequencies will be reflected back by the ionospheric layer having electron density 1011 m-3?(a) 2 MHz (b) 10 MHz (c) 12 MHz (d) 18 MHz

Answer»

(a) 2 MHz

Critical frequency,

f_c = 9 (N_max)^1/2

= 9(10¹¹)^1/2 = 2.8 x 10⁶ Hz = 2.8 MHz

∴ The wave of frequency 2 MHz will be reflected by the ionosphere.