One type of electron microscope, called a scanning electron microscope (SEM), forms an image of the surface of an object by focusing electrons to a small spot on the object and then measuring the yield of reflected electrons. 

(a) If the electron energy is 100 keV, what is the electron wavelength? 

(b) Based on our discussion of light microscopes in Chapter 26, what resolution do you expect to achieve with this SEM? That is, what is the approximate size of the smallest object that you expect to resolve? Due to other limitations, SEMs do not achieve this resolution.