Question
The wavelength of an electron moving with velocity of $${10^7}\,m\,{s^{ - 1}}$$ is
A.
$$7.27 \times {10^{ - 11}}\,m$$
B.
$$3.55 \times {10^{ - 11}}\,m$$
C.
$$8.25 \times {10^{ - 4}}\,m$$
D.
$$1.05 \times {10^{ - 16}}\,m$$
Answer :
$$7.27 \times {10^{ - 11}}\,m$$
Solution :
$$\eqalign{
& \lambda = \frac{h}{{mv}} \cr
& \,\,\,\,\, = \frac{{6.626 \times {{10}^{ - 34}}J\,s}}{{9.11 \times {{10}^{ - 31}}\,kg \times {{10}^7}\,m\,{s^{ - 1}}}} \cr
& \,\,\,\,\, = 7.27 \times {10^{ - 11}}\,m \cr} $$