Question
What do you mean by background radiations? Name its sources. Is it possible for us to keep ourselves away from it?

Answer

The low temperature microwave radiation that arrives at the earth's surface from all directions of outer space is called background radiation.
Sources of background radiations are:
(a) Radiation from the sun.
(b) Rocks in the earth which contain traces of radioactive substances.
(c) Naturally occurring isotopes.
(d) Artificial radioisotopes.
No, it is not possible to keep ourselves away from these radiations.

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