Question #6a4bb

1 Answer
Oct 23, 2017

Energy of a photon of wavelength lambda_p is given by the expression

E_p=(hc)/lambda_p ......(1)

de Brogile wavelength of an electron is expressed as

lambda_e=h/p_e
=>p_e=h/lambda_e ........(2)

Kinetic energy equation for a particle can also be written as

KE=p^2/(2m)

Using (2), for electron

KE_e=(h/lambda_e)^2/(2m)

Given that wavelength of a photon and the de Brogile wavelength of an electron has same value. Let it be equal to lambda. Re-writing above with the help of (1) we get

KE_e=(h/lambdaxxE_p/c)/(2m)
=>KE_e=(hE_p)/(2lambdamc)

=>E_p=(2lambdamc)/hxxKE_e