The de - Broglie wavelength of a particle moving with a velocity `2.25 xx 10^(8) m//s` is equal to the wavelength of photon. The ratio of kinetic energy of the particle to the energy of the photon is (velocity of light is `3 xx 10^(8) m//s`

Options

A. `1//8`
B. `3//8`
C. `5//8`
D. `7//8`

Answer

B

Explanation

`E_(K)/E_(P)=((mv^(2))/2)/((hc)/lambda)=(mv.v)/2 xx lambda /(hc)`
`=h/lambda . v/2 xx lambda /(hc)`
`=h/lambda . v/2xxlambda/(hc)`
`=v/(2c)=(2.25xx10^(8))/(3xx10^(8))=3/8`