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    Hi, I have a graph here of the photoelectric effect, the y intercept is the work function, but what I don't understand is how can the work function be negative? That would mean the material needs negative energy which isn't possible for the photoelectric effect to occur?
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    (Original post by ᒍack)
    Hi, I have a graph here of the photoelectric effect, the y intercept is the work function, but what I don't understand is how can the work function be negative? That would mean the material needs negative energy which isn't possible for the photoelectric effect to occur?
    from the y-intercept to the point where y=0 that is the energy of the work function, look at the x-axis. It's not negative energy, it's energy that needs to be gained.
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    (Original post by Mikasadoge)
    from the y-intercept to the point where y=0 that is the energy of the work function, look at the x-axis. It's not negative energy, it's energy that needs to be gained.
    Ah ok, It's just i had Ekmax = hf - work function so when i'm plotting it, the work function is in the negatives on the graph.
    So from what you're saying the work function is actually the difference between 0 on the y axis and the point at which it intercept? and that it will always be positive?
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    (Original post by ᒍack)
    Ah ok, It's just i had Ekmax = hf - work function so when i'm plotting it, the work function is in the negatives on the graph.
    So from what you're saying the work function is actually the difference between 0 on the y axis and the point at which it intercept? and that it will always be positive?
    yeah if I'm imagining the same graph as you. Hope it made sense
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    (Original post by Mikasadoge)
    yeah if I'm imagining the same graph as you. Hope it made sense
    This is a google image of a the same graph, and yes it did thanks, it confused me a little, just clicked in my head then

    https://www.google.co.uk/search?q=ph...5XyOYAlNCcorM:
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    (Original post by ᒍack)
    This is a google image of a the same graph, and yes it did thanks, it confused me a little, just clicked in my head then

    https://www.google.co.uk/search?q=ph...5XyOYAlNCcorM:
    yep looks good to me, you're welcome
 
 
 
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