Finding Maximum kinetic energy of ejected electrons

AI Thread Summary
To find the maximum kinetic energy of ejected electrons, the photoelectric effect must be considered, using the equation E = hc/λ to calculate the energy of the incoming photons. The maximum kinetic energy can be determined by subtracting the work function (related to the cutoff potential) from the photon energy. In this case, the energy of the yellow light with a wavelength of 578 nm and a frequency of 5.19 x 10^14 Hz needs to be calculated first. The cutoff potential of 0.25 V indicates the minimum energy required to eject an electron, which must be converted to joules or electron volts for comparison. Understanding these principles is crucial for correctly solving the problem.
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Homework Statement


So i know the light colour, wavelength, cutoff potential and frequencies. I am trying to find the maximum kinetic energy of the ejected electrons(J or eV)
heres the first set of numbers for the colour of yellow:
wavelength 578nm(5.78 x 10 to the -7metres). cutoff potential 0.25v. Frequency= 5.19 x 10 to the 14 HZ

Homework Equations


E= hc/λ


The Attempt at a Solution


so i started to think that i was supposed to use the equation e=hc/λ. but it is not getting me the right answer. i think this might be because the "E" is just total energy and not kinetic, but i have no idea what to do. Please help
 
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