An electron of mass `m` and a photon have same energy `E`. The ratio of de - Broglie wavelengths associated with them is :

Options

A. `1/c(E/(2m))^(1/2)`
B. `(E/(2m))^(1/2)`
C. `c(2mE)^(1/2)`
D. `1/c((2m)/E)^(1/2)`

Answer

a

Explanation

For electron, `lambda_(e)=h/(sqrt(2mE))`
For photon: `lambda_(p)=(hc)/E`
`(lambda_(e))/(lambda_(p))=h/(sqrt(2mE))xxE/(hc)=1/2sqrt(E/(2m))`