Photoelectric Effect: Current & Voltage Effects

AI Thread Summary
Doubling the intensity of light while keeping the frequency constant results in a doubled current but no change in voltage. When the intensity is constant and the frequency is doubled, the current remains unchanged, but the voltage increases. The relationship between intensity and the number of photons is highlighted, while frequency relates to photon energy. The discussion emphasizes the need to consider the work function when analyzing voltage changes with frequency adjustments. Overall, the answers provided are generally correct, but further mathematical consideration regarding voltage is encouraged.
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Homework Statement



1. If frequency is constant and intencity of light is doubled what happen to the current?
2. If frequency is constant and intencity of light is doubled what happen to the voltage?
3. If intencity is constnat and frequency of light is doubled what happen to the current?
4. If intencity is constnat and frequency of light is doubled what happen to the voltage?

Homework Equations



E = hf

The Attempt at a Solution



I know the intencity of light is proportional to the number of photons
and frequency of light is is proportional to the energy of photons
So my answer is

1. current doubled
2. no change
3. no change
4. voltage doubled

am I right?
 
Physics news on Phys.org
yes, you are, though would the voltage be exactly doubled with the frequency bieng doubled? Think about the work function and try it mathematically.
 
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