JEE Main202118 Mar 2021Evening ShiftPhysicsNuclear PhysicsActual
The decay of a proton to neutron is :
Options
- Anot possible as proton mass is less than the neutron mass
- Bpossible only inside the nucleus
- Cnot possible but neutron to proton conversion is possible
- Dalways possible as it is associated only with β + decay
Correct answer
B. possible only inside the nucleus
Step-by-step solution
It is possible only inside the nucleus and not otherwise as it can not decay to a state of greater mass. Inside a nucleus however, the situation is different, as the binding energy of a nucleus provides the necessary energy to compensate for the neutron-proton mass difference.