\(\,{M_P}{V_P} = \bar P = \frac{c}{{20}} \times {M_P}\)
\(\lambda = \frac{h}{P} = \frac{{6.6 \times {{10}^{ - 34}} \times {{10}^{ - 15}}}}{{3 \times {{10}^8} \times 1.69 \times {{10}^{ - 24}}}}m\,\)
\( = \frac{{20 \times 6.6}}{{1.67 \times 3}} \times {10^{ - 15}}m = 2.64 \times {10^{ - 14}}m\)