A $γ$ -ray photon creates an electron-positron pair. The rest mass equivalent of electron is 0.5 MeV. KE of the electron - positron system is 0.78 MeV. Then the energy of $γ$ -ray photon is

1.78 M e V

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

0.28 M e V

No worries! We‘ve got your back. Try BYJU‘S free classes today!

1.28 M e V

No worries! We‘ve got your back. Try BYJU‘S free classes today!

0.14 M e V

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Open in App

Solution

The correct option is B $1.78 M e V$
The rest mass of electron is $= 0.5 M e V$
As, the momentum is conserved the rest mass of positron should also be $0.5 M e V$ .
The kinetic energy of the pair is $0.78 M e V$ .
$∴$ The energy of $γ$ ray photon is $= (0.5 + 0.5 + 0.78) M e V = 1.78 M e V$

Suggest Corrections

Similar questions

Q. A gamma ray photon creates an electron, positron pair. If the rest mass energy of an electron is 0.5 MeV and the total KE of the electron, positron pair is 0.78 MeV, then the energy of the gamma ray photon must be :

Q. A gamma ray photon creates an electron-positron pair. If the rest mass energy of an electron is

0.5 M e V

and the total kinetic energy of the electron-positron pair is

0.78 M e V

, then the energy of the gamma ray photon must be :

Q. A

γ

ray photon produces an electron positron pair. If the rest mass energy of electron is

0.51 M e v

and the total kinetic energy of electron - positron pair is

0.78 M e V

then the energy of

γ

- ray photon is

M e v

The rest mass energy of an electron as well of an positron is 0.51 MeV. If a $γ$ -photon of energy 2.42 MeV produces an electron – positron pair, then the kinetic energy of each particle is

Q. If the rest mass of an electron or positron is

0.51 M e V

, then the kinetic energy of each particle, in the electron-positron pair produced by a

γ -

photon of

2.42 M e V

, will be ?

Join BYJU'S Learning Program

A γ -ray photon creates an electron-positron pair. The rest mass equivalent of electron is 0.5 MeV. KE of the electron - positron system is 0.78 MeV. Then the energy of γ -ray photon is

The correct option is B 1.78MeVThe rest mass of electron is =0.5 MeVAs, the momentum is conserved the rest mass of positron should also be 0.5 MeV. The kinetic energy of the pair is 0.78 MeV.∴ The energy of γ ray photon is =(0.5+0.5+0.78) MeV=1.78 MeV

A $γ$ -ray photon creates an electron-positron pair. The rest mass equivalent of electron is 0.5 MeV. KE of the electron - positron system is 0.78 MeV. Then the energy of $γ$ -ray photon is

The correct option is B $1.78 M e V$
The rest mass of electron is $= 0.5 M e V$
As, the momentum is conserved the rest mass of positron should also be $0.5 M e V$ .
The kinetic energy of the pair is $0.78 M e V$ .
$∴$ The energy of $γ$ ray photon is $= (0.5 + 0.5 + 0.78) M e V = 1.78 M e V$