If the momentum of an electron is changed by `p`, then the de - Broglie wavelength associated with it changes by `0.5 %`. The initial momentum of electron will be

Options

A. `200 p`
B. `400 p`
C. `(p)/(200)`
D. `100 p`

Answer

A

Explanation

de - Broglie wavelength `lambda = (h)/(p)`
Here `|(Delta lambda)/(lambda)| = |(Delta p)/(p)|`
`(0.5)/(100) = (p)/(p_(i))`
`p_(i) = (100)/(0.5) p`
`p_(i) = 200 p`