\(\therefore v = \sqrt {\frac{{2 \times 0.0837 \times 1.6 \times {{10}^{ - 19}}}}{{1.675 \times {{10}^{ - 27}}}}} = 4 \times 10^3 \,m/sec\) 

\(\therefore \Delta t' = \frac{{40}}{{4 \times {{10}^3}}} = {10^{ - 2}}sec\)

\(\frac{{dN}}{{dt}} = \lambda \,N\)

\(⇒\frac{{dN}}{N} = \lambda \,dt\)

\(\therefore \) અવિભંજીત ભાગ \(\frac{{\Delta N}}{N} = \lambda \,\Delta t = \frac{{0.693}}{T}\Delta t = \frac{{0.693}}{{693}} \times {10^{ - 2}} = {10^{ - 5}}\)