Photoelectric effect and work function

AI Thread Summary
The discussion focuses on identifying the plot representing the metal with the lowest work function and understanding the significance of the graph's slope. The plot with the lowest work function is identified as plot 1, as it corresponds to the lowest frequency needed for the photoelectric effect to occur. The slope of the graph represents Planck's constant, indicating a constant energy-to-frequency relationship across different materials. Additionally, the relationship between backing volts and light frequency, independent of intensity, is highlighted as a key point for further explanation. Understanding these concepts is essential for grasping the photoelectric effect and its implications in physics.
stickplot
Messages
83
Reaction score
0

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

  • PhyU08gradegraph.gif
    PhyU08gradegraph.gif
    4.1 KB · Views: 804
Physics news on Phys.org
I can't see the graph but if its kinetic energy versus frequancy then there will be a straight line relationship.

T = h\nu -\phi

Compare that with the equation of a straight line y=mx+c.
 
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?
 
Looks good. For b all you need say is it represents Planck's constant.
 
alright thank you
 
Explain why the backing volts depends on the frequency of light but not on the intensity.
 
TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
Thread 'Variable mass system : water sprayed into a moving container'
Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
Back
Top