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According to Einstein's theory of relati...

According to Einstein's theory of relativity, mass can be converted into energy and vice-versa. The lightest elementary partical, taken to be the electron, has a mass equivalent to `0.51 MeV` of energ. Then, we can say that

A

the minimum amount of energy avalible through conversition of mass into energy is `1.2 MeV`

B

the least energy of a `lambda`ray photon that can be converted into mass is `1.02 MeV`

C

whereas the minimum energy released by conversion of mass into energy is `1.02 MeV`, it is only a `lambda`- ray photon of energy `0.51 MeV` and above that can be converted into mass

D

whereas the minimum energy released by conversion of mass into energy is `0.51 MeV`, it is only a `lambda`- ray photon of energy `1.01 MeV` and above that can be converted into mass

Text Solution

Verified by Experts

The correct Answer is:
A, B
The correct choices are (a) and (b). The last two statements are incorrect because they violate the principal of conservation of charge. We always have either an electron- positron 'pair production` or an electron- positron 'pairannihilation`. It is only then that the total charge remains zero both before and after reaction.
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