Photoelectric Effect and stopping potential

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Homework Help Overview

The discussion revolves around the photoelectric effect, specifically analyzing the stopping potential of light of different wavelengths striking a metal surface. The original poster presents a scenario involving 445 nm and 410 nm light and their respective stopping potentials.

Discussion Character

  • Exploratory, Assumption checking

Approaches and Questions Raised

  • The original poster attempts to relate the stopping potentials of two different wavelengths of light and considers the energy equations involved. Some participants question whether the work function of the metal has been accounted for in the calculations.

Discussion Status

The discussion is ongoing, with participants seeking clarification on the original poster's approach and emphasizing the need to consider the work function. There is a request for the original poster to show their efforts and retry the problem with this consideration in mind.

Contextual Notes

There is mention of a textbook table that may provide additional context for identifying the metal based on the calculated work function. The original poster's question appears to have been partially cut off, leading to some confusion in the discussion.

Turion
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Homework Statement



When 445 nm light strikes a certain metal surface, the stopping potential is 70% of that which results when 410 nm light strikes the same metal.

Homework Equations





The Attempt at a Solution



$$P=0.7P'\\ \frac { nE }{ t } =\frac { 0.7nE' }{ t } \\ \frac { hc }{ λ } =\frac { 0.7hc }{ λ' } \\ \frac { λ' }{ λ } =0.7$$
 
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And the question is?
Oh and you are neglecting the work function of the metal- I think
 
Opps. I didn't realize the question was cut off.

Here's the second part:

Based on this information and the table given in the textbook, identify the metal.

Basically, what is required is to calculate the work function.

A: work function 2.23 eV. Potassium.
 
Turion said:
bump

Show your effort please. As suggested, did you take the work function into account? Retry the problem.
 

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