Photoelectric effect and work function

In summary, the conversation discusses the relationship between work function and frequency in a photoelectric effect, as well as the significance of the slope on a kinetic energy vs frequency graph. It is determined that the plot with the lowest work function on the graph is the one with the lowest frequency, and the slope of the graph represents Planck's constant. The conversation also briefly touches on the relationship between backing volts and the frequency of light, noting that it is dependent on frequency but not on intensity.
  • #1
stickplot
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Homework Statement



a. Which plot on the graph represents the metal with the lowest work function?

b. What does the slope of the graphs represent? (graph is attached)

Homework Equations



threshold frequency= work function/ planks constant

The Attempt at a Solution



a. the lower the work function, the lower the frequency, so (im still confused about the graph)
so plot 1 is the one with the lowest work function.
b. the slope on the graph shows the amount of energy frequency that it took for a photoelectric effect to occur.

im not to sure about my answers someone help out please.
 

Attachments

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  • #2
I can't see the graph but if its kinetic energy versus frequancy then there will be a straight line relationship.

[tex] T = h\nu -\phi [/tex]

Compare that with the equation of a straight line [itex]y=mx+c[/itex].
 
  • #3
o ok i got it
i understand the graph now. it is a kinetic energy vs frequency graph.

a. the plot with the lowest work function is 1, because it supports the least amount of frequency. The one that supports the least amount is the one that causes a photoelectric effect first
b. the three slopes are equal to Planck's Constant which shows that the energy to frequency relation is constant for all materials. It also shows the difference between each one and compare how much threshold frequency they each support.

how is that?
 
  • #4
Looks good. For b all you need say is it represents Planck's constant.
 
  • #5
alright thank you
 
  • #6
Explain why the backing volts depends on the frequency of light but not on the intensity.
 

Related to Photoelectric effect and work function

What is the photoelectric effect?

The photoelectric effect is the phenomenon where electrons are emitted from a material when it is exposed to light of a certain frequency or higher. This was first observed by Heinrich Hertz and later explained by Albert Einstein through his theory of photons.

How does the photoelectric effect support the particle nature of light?

The photoelectric effect demonstrates that light is made up of individual particles, or photons, rather than being a continuous wave. This is because the number of electrons emitted from a material is directly proportional to the intensity of the light, but the energy of the electrons is dependent on the frequency of the light, not its intensity.

What is the work function in the photoelectric effect?

The work function is the minimum amount of energy required to eject an electron from the surface of a material. It is different for each material and is dependent on factors such as the type of material, its surface properties, and the frequency of the incident light.

What is the significance of the threshold frequency in the photoelectric effect?

The threshold frequency is the minimum frequency of light required to eject an electron from a material. If the frequency of the incident light is below the threshold frequency, no electrons will be emitted regardless of the intensity of the light. This supports the idea that the energy of the electrons is dependent on the frequency of the light, not its intensity.

What are some practical applications of the photoelectric effect?

The photoelectric effect has many practical applications, including solar panels, photodiodes, and photomultiplier tubes. It is also used in devices such as photocells, which are used to automatically turn lights on and off, and in digital cameras, where it is used to convert light into electrical signals.

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