Question

Some of the properties of a microwave are mentioned here. Select the incorrect option.
1. Microwaves are reflected by Ionosphere
2. Microwaves travel in a straight line and are reflected by the conducting surfaces.
3. Microwaves are the waves that radiate electromagnetic energy with shorter wavelength
4. Microwave currents can flow through a thin layer of a cable.

Answer 1

Correct Answer - Option 1 : Microwaves are reflected by Ionosphere

Option(1) Explanation-

Microwaves are not reflected back to the surface of the Earth by ionosphere.

They pass through the ionosphere and are received by satellites orbiting the Earth. The satellite amplifies the signal and then re-transmits the signal back to Earth. So it is correct option.

Radio waves can be reflected from ionosphere.

Option(2) Explanation-

Any metal (conductor) will reflect radio and microwaves, but a highly polished metal like silver or gold would reflect microwaves better.

Option(3) Explanation-

Microwave is a form of electromagnetic radiation with wavelengths ranging from about one meter to one millimeter corresponding to frequencies between 300 MHz and 300 GHz respectively.

Radio waves are EM (Electromagnetic)waves that have wavelengths between 1 millimeter and 100 kilometers (or 300 GHz and 3 kHz in frequency).

So Microwaves are electromagnetic waves with wavelengths longer than those of terahertz (THz) wavelengths, but relatively short for radio waves.

Option(4) Explanation-

Microwave currents can flow through a thin layer of a cable.