Question
An electron and its antiparticle are annihilated after collision. How much energy will be obtained? What will be the wavelength of the emitted radiation (energy)? (Mass of electron , speed of light and Planck’s constant )

0.75 Å

0.45 Å

0.024 Å

None of these
medium
Solution
0.024 Å
The annihilation equation is
(electron) (positron)
The mass annihilation in this process is
According to energymass relation, the energy released is
= 1.02 MeV.
Tow photon are produced in this process, hence energy of each photon is
.
The wavelength corresponding to it is
= 0.024 Å.
SIMILAR QUESTIONS
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