Q.What is the wavelength of a beam of electron traveling at 2 x 10^6 cm/s?
A: 3.64 x 10 ^ -6
Now we have the mass of electron: 9.109 x 10^-31 kg
and we have the formula: E= hc/lambda and/or c= v x lambda
but I am not exactly sure of how to solve it? Do we need the mass of an electron? How do you go about it? The answer is above, but I am not sure of the way to answer it. Immediate help would be GREATLY APPRECIATED!