Question

What type of invisible radiation from space that can be detected from earth’s surface?
A.Gamma rays
B.X-rays
C.Infrared waves
D.Radio waves.

Answer 1

Hint: Radiation is a form of energy from a source that travels through space or other mediums.Light, heat, microwaves, radio, television, etc are all forms of radiation. They are made up of particles and electromagnetic waves and they carry energy.

Complete answer:
Radiations are of many types, they are produced by various particles(especially ions). Few of them are X-rays, gamma-rays, alpha particles, beta particles, etc.
Let us discuss about the above given options in detail.:
-Gamma rays: they have the smallest wavelengths. They are produced by the hottest and the most energetic compounds In the universe, they are generally produced by neutrons, stars , supernovas, etc.
-X-rays: these are electromagnetic waves very small in size(in nanometers). These rays are produced to inner capture by the nucleus of an atom. Another source is wg=hen a metal is bombarded by electrons.
-Infrared radiation (IR): all hot bodies emit this radiation . The wavelength of these waves is about 700nm to 1mm. These are emitted by the hot bodies in the universe and at=re invisible.
-Radio waves: these are the waves generated by accelerating charged particles in electromagnetic fields. Their wavelengths are more than 1mm.
Hence looking at all the above details, we see that the correct answer to this question is infrared-waves, that is option C.

Note:
The infrared waves and gamma rays both are produced in space and both are detected by earth’s surface, but the wavelengths of infrared waves are more than visible radiation( 400nm to 700nm) . hence this is the correct answer and not gamma rays.