Question about 1.33

[Joe Rich 1D]

The question asks for the wavelength of an electron that was ejected from a metal surface with a velocity of 3.6 x 10^-3 km/s. I know that one way to solve this is by using the De Broglie equation, but I was just wondering if it was possible to solve this by solving for Kinetic Energy of the electron (KE=0.5mv^2), and plugging this energy into the equation E=vh/λ. Thanks!

[Dabin Kang 1B]

The question doesn't ask for the wavelength of an ejected electron. It asks for the wavelength of the photon that caused the ejection of an electron.

[Joe Rich 1D]

Part a actually does ask for the wavelength of the electron I think.

[Dabin Kang 1B]

Oh, I thought you were asking about part C. You would use to solve for the wavelength. How did you get E=vh/λ ?

[Joe Rich 1D]

I was wondering if you could use the same type of equation as you do for light to relate energy and wavelength, which is E=hc/λ. But instead of using the speed of light, I would substitute in the velocity of the particle. I wasn't sure whether this was a valid technique or not though.