Photoelectric effect, and sunlight.

AI Thread Summary
The discussion centers on whether sunlight has sufficient intensity to eject electrons from metal atoms through the photoelectric effect. It clarifies that while sunlight has a high enough frequency, visible light alone cannot knock out electrons; ultraviolet light is typically required for this effect. The intensity of light influences the number of electrons emitted but not the ability to eject them, which depends on frequency. Additionally, atmospheric conditions block much of the UV radiation, limiting its effectiveness. Overall, the conversation highlights the importance of frequency over intensity in the context of the photoelectric effect.
kcajrenreb
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Hello, I apologize if this question makes no sense, or is stupid, but I would just like to clarify something.

Is the light that comes from the sun a high enough intensity to "knock" any electrons out of the atoms in a metal? I know it is a high enough frequency, and I think the intensity is high enough, but I'd just like to make sure.

Thank you very much, and again I apologize if my question made little sense.
 
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The photoelectric effect is independent of intensity. A single photon can knock an electron out of metal as long as the frequency is high enough, aka it has enough energy. Intensity merely causes MORE electrons to be knocked out per unit of time.
 
kcajrenreb said:
Hello, I apologize if this question makes no sense, or is stupid, but I would just like to clarify something.

Is the light that comes from the sun a high enough intensity to "knock" any electrons out of the atoms in a metal? I know it is a high enough frequency, and I think the intensity is high enough, but I'd just like to make sure.

Thank you very much, and again I apologize if my question made little sense.

Visible light cant.
X-ray i think can knock out an electron of almost everything.
The problem is if they can get to your metal. most of UV and higher get blocked by the atmosphere.
 
Really? I thought that blue light on the visible spectrum was a high enough frequency to "knock" the electrons out of metal, I guess I thought wrong. Thanks for your answers both of you.
 
kcajrenreb said:
Really? I thought that blue light on the visible spectrum was a high enough frequency to "knock" the electrons out of metal, I guess I thought wrong. Thanks for your answers both of you.

From wikipedia:
When a surface is exposed to electromagnetic radiation above a certain threshold frequency (typically visible light for alkali metals, near ultraviolet for other metals, and extreme ultraviolet for non-metals), the radiation is absorbed and electrons are emitted. Light, and especially ultra-violet light, discharges negatively electrified bodies with the production of rays of the same nature as cathode rays.

The article is here:http://en.wikipedia.org/wiki/Photoelectric_effect
 

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