Photoelectric effect and photocurrent drop

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SUMMARY

The discussion centers on the behavior of photocurrent in relation to applied potential in a photoelectric effect experiment. It was observed that the photocurrent did not drop to zero even when the potential across the anode and cathode was increased negatively, suggesting that the current reached a steady state. The experiment utilized various wavelengths, including yellow, turquoise, green, blue, and violet, and the relationship between photocurrent and potential was expected to resemble a 1/x graph. The participants debated the implications of extrapolating data to predict zero current.

PREREQUISITES
  • Understanding of the photoelectric effect
  • Familiarity with photocurrent measurement techniques
  • Knowledge of voltage application in electron emission experiments
  • Ability to interpret graphical data and curve fitting
NEXT STEPS
  • Research the relationship between photocurrent and potential in photoelectric experiments
  • Learn about the effects of different wavelengths on photocurrent generation
  • Study the principles of curve fitting and extrapolation in experimental data analysis
  • Investigate the impact of anode and cathode voltage configurations on electron behavior
USEFUL FOR

Students and researchers in physics, particularly those studying the photoelectric effect, as well as educators seeking to understand experimental outcomes related to photocurrent behavior.

hayyan1
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Homework Statement



Does the photocurrent drop to zero when a potential across it is equal to the kinetic energy of electrons?, because i found this not to be the case, the photocurrent reached a steady value that didnt decrease further, as i increased the potential across the anode and cathode. I don't understand why this happened?
 
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Was the anode at + or - relative to the cathode?
 
anode voltage was increased negatively so electron should be repelled from anode in theory, but for some reason i still was obtaining positive photocurrent, maybe i should have taken much larger negative values for potential, so current would eventually become zero?, however do you think i can extrapolate (with a curve of best fit) to zero current, because my graphs are curving towards zero photocurrent.
 
It depends. What wavelength(s) was/were used to generate the photocurrent? How high a voltage did you get to?

Extrapolating reasonably depends on whether graphing the data generates a straight line. Does it?
 
I used yellow, turquoise, green, blue, violet. it isn't ment to generate a straight line, for each frequency, the photocurrent (yaxis) is kind of meant to drop like a 1/x graph when plotted against the potential across the xaxis
 
That's weird. I would expect current to be zero if you go high enough in voltage, but I haven't done the experiment.

Not sure what's going on.
 

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