In a gamma decay process, the internal energy of a nucleus of mass M decreases, a gamma photon of energy E and linear momentum E/c is emitted and the nucleus recoils. Find the decrease in internal energy.

Given that the internal energy of a nucleus of mass M decreases,


Gamma photon energy is E,


Linear momentum is E/c and the nucleus recoils.


j40.PNG


Then, kinetic energy (K.E) of nucleus is





Energy limited by gamma photon is E


Thus, decrease in internal energy will be equal to sum of energy limited by gamma photon and kinetic energy of nucleus.


So, Decrease in internal energy,



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