Hi everyone! I've got a question. I have this problem and I want some help because I couldn't with it.
The threshold frequency for shedding an electron from the cesium surface
metallic is 5.18 x 10¹⁴ s⁻¹. Calculate:
- The energy of a photon of this frequency
- The energy of a photon of light of wavelength 400 nm
- The kinetic energy of an electron that gives off cesium from the surface
a beam of light with a wavelength of 400 nm.
For the first one I used the equation E=hv
, for the second I used E = h*c/λ
and the last one kinetic energy = h (photon frequency - threshold frequency)
But I get negative kinetic energy (-3.93x10⁻¹⁹ to be exacts)
. Am I doing something wrong? How would it be the right way to solve this problem?
Thank you for taking the time to read and answer me<3!