Question

If the momentum of electron is changed by P, then the de Broglie wavelength associated with it changes by 0.5%. The initial momentum of electron will be(a) 200 P(b) 400 P(c) P/200(d) 100 P

Answer 1

Answer:

A) 200P

Explanation:

Change in momentum of electron = P (Given)

Change after association with de Broglie = 0.5% (Given)

According to de Broglie method, the wavelength associated with an electron is described as -

λ = h/P or P = h/λ

Thus,

dλ / λ= – dp / P  ( -ve sign shows that the change will be opposite to change in wavelength)

0.5 / 100 = P / P’

P’ = 200 P

Thus, the initial momentum of electron will be 200P