A free neutron beta-decays to a proton with a half-life of 14 minutes.
(a) What is the decay constant?
(b) Find the energy liberated in the process.
a) Given, half-life = 14 minutes = 840 seconds
We know, half life 
, where λ = decay constant
= 8.25×10-4 s-1
b) 
[equation of neutron undergoing β decay]
Energy 
Mn = mass of Neutron
Mp = mass of proton
Mβ = mass of β-particle
c2= (Speed of light)2 = 931.5 MeV/u
= 782.83 KeV
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