Chemistry
posted by Anonymous on .
To resolve an object in an electron microscope, the wavelength of the electrons must be close to the diameter of the object. What kinetic energy must the electrons have in order to resolve a protein molecule that is 2.10 nm in diameter? Take the mass of an electron to be 9.11× 10–31 kg.
=_____J

wavelength = h/mv
Substitute and solve for v, then substitute v into KE = 1/2 mv^2 and solve for KE. 
λ=h/mv
2.10*10^9=(6.63*10^34)/(9.11*10^31)v
(1.91*10^39)v=6.63*10^34
v=347120.42
k=1/2mv^2
k=1/2(9.11*10^31)(347120.42)^2
k=5.49*10^20