HW question 15

[505934309]

On question 15 I am having trouble converting to eV. Can someone walk me through what they did?

[Angie Sun 2E]

For the question, first use the given wavelength (convert it to meters first) and use De Broglie's wavelength equation to solve for the velocity of the electron. Then, use the kinetic energy equation (1/2 mv^2) to plug in the velocity and obtain the KE in J. We know 1 ev = 1.602 x 10^-19 J, so use dimensional analysis to divide your answer in J by 1.602 x 10^-19 J to get eV.