A star initially has deuterons

PHYSICS · Single correct · CBSE · Physics · Nuclei · Nuclei

Problem

A star initially has

10^{40}

deuterons. It produces energy via the processes

{}_1^2\text{H}+{}_1^2\text{H}\to{}_1^3\text{H}+p

and

{}_1^2\text{H}+{}_1^3\text{H}\to{}_2^4\text{He}+n.

The nuclear masses are

m({}_1^2\text{H})=2.014\,\text{amu}

m(p)=1.007\,\text{amu}

m(n)=1.008\,\text{amu}

, and

m({}_2^4\text{He})=4.001\,\text{amu}

. If the average power radiated by the star is

10^{16}\,\text{W}

, the deuteron supply is exhausted in a time of the order of: (1)

10^6\,\text{s}

(2)

10^8\,\text{s}

(3)

10^{12}\,\text{s}

(4)

10^{16}\,\text{s}