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Hapablap
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*Edit: Nevermind, I realize where I went wrong!
The following graph shows the kinetic energy of the most energetic photoelectrons as a function of the frequency of light falling on the cathode in a photoelectric cell.
http://img208.imageshack.us/img208/3421/fwby.jpg
Use the graph to determine the value of Planck's constant.
E = hf
h = E/f
I'll choose the point where E = 3.0 eV and f = 10.0 Hz for my calculation.
First I'll convert eV to Joules:
3.0 eV x (1.60 x 10^-19 J / 1 eV) = 4.8 x 10^-19 J
Now the calculation:
h = E/f
h = (4.8 x 10^-19 J) / (10.0 x 10^14 Hz)
h = 4.8 x 10^-34 J(s)
We already know that the value of Planck's constant is 6.63 x 10^-34 J(s), so my answer is off.
Any suggestions?
Homework Statement
The following graph shows the kinetic energy of the most energetic photoelectrons as a function of the frequency of light falling on the cathode in a photoelectric cell.
http://img208.imageshack.us/img208/3421/fwby.jpg
Use the graph to determine the value of Planck's constant.
Homework Equations
E = hf
h = E/f
The Attempt at a Solution
I'll choose the point where E = 3.0 eV and f = 10.0 Hz for my calculation.
First I'll convert eV to Joules:
3.0 eV x (1.60 x 10^-19 J / 1 eV) = 4.8 x 10^-19 J
Now the calculation:
h = E/f
h = (4.8 x 10^-19 J) / (10.0 x 10^14 Hz)
h = 4.8 x 10^-34 J(s)
We already know that the value of Planck's constant is 6.63 x 10^-34 J(s), so my answer is off.
Any suggestions?
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