An X ray beam has a wavelength of 0.010 Å. What is its momentum ? `(h=6.63 xx10^(9-34) J-s)`

Options

A. `6.63xx10^(-22) kg m//sec`
B. `3.45xx10^(-25) kg m//sec`
C. `3.31xx10^(-22) kg m//sec`
D. `2.12xx10^(-23) kg m//sec`

Answer

A

Explanation

The beam of X rays contains X ray photons.
The momentum of a photon `P= h/lamda`
In this case `lamda = 0.01 Å = 10^(-12) m (1Å = 10^(-10) m )`
`therefore P = (6.63xx10^(-34))/(10^(-12)) = 6.63xx10^(-22) kg m//s`