Which atmospheric layer deflects the radio waves having the frequency greater than 50 MHz?
(A) Stratosphere
(B) Mesosphere
(C) Ionosphere
(D) Troposphere
Correct Ans: (C)
In the field of mass communication and electronic transmission, understanding how signals travel is essential. One important layer of the atmosphere that plays a significant role in this is the ionosphere. This layer lies above the mesosphere and contains a high concentration of ions and free electrons.
Now, when it comes to radio waves with frequencies above 50 MHz, the ionosphere deflects or refracts them. This happens due to the ionized particles in that layer, which interact with electromagnetic waves. Therefore, signals such as shortwave and FM radio transmissions get affected by this natural barrier.
Moreover, the ionosphere doesn’t reflect very high-frequency waves like satellite or GPS signals. Instead, it allows them to pass through. However, in the range just above 50 MHz, the ionosphere can still bend or scatter these signals, depending on the atmospheric conditions. This is why the ionosphere becomes a critical factor in long-distance communication, especially in early radio technologies and even in modern broadcasting.
In contrast, the troposphere and stratosphere have little impact on such radio waves. They affect weather patterns or ultraviolet radiation more than communication. As for the mesosphere, it’s too sparse and doesn’t contribute significantly to wave deflection.
To conclude, the ionosphere plays a vital role in shaping radio wave behavior. It influences how we receive radio, TV, and even satellite signals, making it indispensable in the study of communication systems.
