\(\Delta L = \frac{h}{{2\pi }}({n_2} - {n_1}) = \frac{{6.6 \times {{10}^{ - 34}}}}{{2 \times 3.14}}(5 - 4)\)
\(\therefore \Delta L= 1.05 \times {10^{ - 34}}\,J-s\)
$\left(\frac{1}{4 \pi \epsilon_0}=9 \times 10^9 \mathrm{SI}\right.$ એકમ $\alpha$ કણનું દળ $=$ $\left.6.72 \times 10^{-27} \mathrm{~kg}\right)$