\(\lambda = \frac{h}{{\sqrt {2mE} }} = \frac{{6.63 \times {{10}^{ - 34}}}}{{\sqrt {2 \times 9.1 \times {{10}^{ - 31}} \times 2.8 \times {{10}^{ - 23}}} }}\,\,\, \Rightarrow \,\,\lambda = 9.28 \times {10^{ - 8}}\,m\)