The speed of an electron having a wavelength of `10^(-10) m` is

Options

A. `4.24xx10^(6)m//s`
B. `5.25xx10^(6)m//s`
C. `6.25xx10^(6)m//s`
D. `7.25xx10^(6)m//s`

Answer

d

Explanation

The de-Broglie wavelength is given by
`lambda=(h)/(p)`
where `h` is Planck's constant and `p` in momentum.
Also `p=mu`
where `m` is mass,`u` is velocity
`u=(h)/(mlambda)`
Putting the numerical values, we have
`h= 6.6xx10^(-34)Js, m=9.14xx10^(-31)Kg`
`lambda=10^(-10)m`
`:. u= (6.6xx10^(-34))/(9.1xx10^(-31)xx10^(-10))`
`u= 7.25xx10^(6)m//s`