Calculate Electron Kinetic Energy: Photon Frequency & Negative Potassium Plate

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A photon with a frequency of 5.8 × 10^14 Hz impacts a negatively charged potassium plate, which has a work function of 3.6 × 10^-19 J. To find the kinetic energy of the ejected electron, the energy of the photon must be calculated using the equation E = hf, where h is Planck's constant. The calculated energy of the photon exceeds the work function, allowing for the determination of the kinetic energy. The final calculated kinetic energy of the electron is 2.454 × 10^-20 J, which is consistent with the expected results. Understanding these concepts is crucial for solving similar physics problems.
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A photon with a frequency of 5.8 × 1014 Hz strikes a clean, negatively charged potassium plate. The work function of potassium is 3.6 × 10-19 J. Calculate the kinetic energy of an electron ejected from the plate by this electron.

Explanation is here i think:

bbc.co.uk/scotland/education/bitesize/higher/physics/radiation/optoelectronics1_rev.shtml

I don't understand anything in physics and I have this home test, and this is the only question I need answered. If you can please help me, I would greatly appreciate it. Thank you ^^
 
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What have you done yourself? That page is very clear and basically gives you all the tools you need to answer the question.
 
I got 2.454x10^-20 J as my final answer
 
Looks ok to me.
 
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