Question

In a process called pair production, an energetic

gamma ray is converted into an electron and
a positron. It is not possible for a gamma ray to be
converted into two electrons because
(1) charge must be conserved
(2) momentum must be conserved
(3) mass-energy must be conserved
(4) baryon number must be conserved

Answer 1

(3) mass-energy must be conserved

Step-by-step explanation:

As we know that gamma rays are mass less and charge less photons which will have sufficient energy.

Now in case of Pair production the gamma photons convert its whole energy into mass by the law of Einstein's mass energy equivalence relation.

As per his relation we can say

`E = \Delta m c^2`

here we will have

[tex]\Delta m[\tex] = mass produced

now we also have to think that here the two particles must have a pair of particles and antiparticles so that the combined mass system will have energy equivalent to the energy of gamma photons and also it must follow the conservation of charge

So here it will form an electron and a positron such that total charge will be zero and the energy will be same as energy of gamma photon.