What is the Correct Way to Calculate the Work Function of a Material?

AI Thread Summary
To calculate the work function of a material, first convert the stopping voltage of 2.30 V into energy units using the equation E = qV, where q is the charge of an electron. The energy of the incident photons can be calculated using the equation hf = hc/wavelength, with a wavelength of 254 nm. The work function is then determined using the equation KE = hf - Wo, where KE is the kinetic energy derived from the stopping voltage. It's essential to ensure that all units are consistent to avoid incorrect results, as improper unit conversion can lead to negative values for the work function, which are not physically meaningful. Accurate calculations are crucial for determining the correct work function of the material.
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Homework Statement



When a monochromatic light with a wavelength of 254 nm falls onto the surface of a particular metal it causes a photocurrent to flow. A stopping voltage of 2.30 V is required to completely block the photocurrent. What is the work function of the material?

Homework Equations


KE = hf - Wo
hf = hc/wavelength


The Attempt at a Solution


I keep getting a negative number which is an impossible answer for a work function.
Any help would be greatly appreciated.

Thank you.
 
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Before solving convert stopping potential to energy units.(J)
Show your calculations.
 
Thanks for pointing that out. I had the wrong units which messed up everything.
 

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