Electron Microscope?

Question

An electron microscope is using a 1.00-keV electron beam. An atom has a diameter of about 10^-19 meters.

QUESTION:

1) What is the wavelength of electrons in this microscope? ____nm

2) Suppose we replace the electron beam with a proton beam. What proton beam. What proton energy is needed to achieve the same resolution as the electron beam in QUestion 1? ____eV

Answer 1

I can only work out the first part, so here goes

Energy = hc / lamda, therefore lamda = hc/E

1keV = 1000 * 1.6x10^-19 Joules = 1.6 x 10^-16

So lamda = (6.626 x 10^-34 * 2.998 x 10^8) / 1.6 x 10-16

= 1.242 nm

Answer 2

Enough for you to not get invited to the hot party Friday night.