Q. The isotope ${ }_{5}^{12} B$ having a mass $12.014 u$ undergoes $\beta$-decay to ${ }_{6}^{12} C .{ }_{6}^{12} C$ has an excited state of the nucleus $\left({ }_{6}^{12} C ^{*}\right.$ ) at $4.041 \,MeV$ above its ground state. If ${ }_{5}^{12} B$ decays to ${ }_{6}^{12} C ^{*}$, the maximum kinetic energy of the $\beta$-particle in units of $MeV$ is. $\left(1 u =931.5 \,MeV / c ^{2}\right.$, where $c$ is the speed of light in vacuum).
JEE AdvancedJEE Advanced 2016
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