The energy of an X-ray photon of wavelength 1.65Å is` (h=6.6xx10^(-34)Js,c=3xx10^(4)ms^(-1),ev=1.6xx10^(-19)J)`

Options

A. 3.5keV
B. 5.5keV
C. 7.5keV
D. 9.5keV

Answer

C

Explanation

The expression for energy of X-ray photon is given as ,
`E=(hc)/(lamda)`
Where,
`(h=6.6xx10^(-34)js,C=3xx10^(8)ms^(-1))`
`implies E=((6.6xx10^(-34))xx(3xx10^(8)))/(1.65xx10^(10))J`
`E=(12xx10^(16))/(1.6xx10^(19))-ev(because 1ev=1.6xx10^(-19))`