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The rest mass of an electron as well as ...

The rest mass of an electron as well as that of positron is 0.51 MeV. When an electron and positron are annihilate, they produce gamma-rays of wavelength(s)

A

0.012 Å

B

0.024 Å

C

`0.012 Å` to `infty`

D

`0.024 Å` to `infty`

Text Solution

Verified by Experts

The correct Answer is:
A
Since electron and positron annihilate
`lamda = (hc)/(E_("Total"))=(6.6 xx10^(-34)xx3xx10^(8))/((0.51+0.51)xx10^(6)xx1.6 xx10^(-19))`
`=1.21 xx10^(-12)m=0.012Å`.
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