I'm a Bioinfo Major (and these are conceptual problems, not HW problems, I have). Please be gentle with your explanation as its been a while since I last studied fusis. Some specific problems I have are:
- What happens to the photon, or the energy/wavelength thereof in Photoelectric Effect (PE) after it gives its energy to eject the electron in the outer shell of the target metal atom in the foil?
- Can we see PE in Graphite and Compton Effect (CE) with a thin metal foil?
- Many websites online say these effects occur are different energies carried by incident photons, if so why exactly is this happening?
I tend to suck at those theory based questions where they ask what happens when intensity is increased, changing frequency with the photocurrent being 0, etc. I hope I make sense in a way, because I don't know shittttt.
Hey!
So I'm currently reading up on the photoelectric effect. My textbook sets the scene for the problem by explaining that Hertz found out that shining light with certain wavelengths on the electrodes in his spark gap experiment created more intense sparks. Further investigating revealed that shining multiple lights on the electrodes did not increase the kinetic energy of the electrons, but instead more electrons were emitted. It then goes on to say that if light is a wave and we increase the intensity of the light, we would expect the electrons to have a higher kinetic energy. But they don't.
I don't understand why these two are at odds with one another. Why could a wave of light not also make the illuminated material emit more electrons rather than increase the energy of the ones struck? Why does this mean that light must be a particle?
Thanks!
If light from a source constantly hits a metal surface, will the surface will become positively charge?
So we've been playing with the PhET photoelectric effect simulation in my physics course and we were asked to find the stopping voltage. The simulation lets you control intensity, wavelength, and voltage and you observe the effect of these parameters on the current.
My work:
- V_stop = KE_max/e.
- KE_max = hc/Ξ» - Ξ¦
- V_stop = hc/(eΞ») - Ξ¦/e
I feel relatively comfortable with this solution, but it's totally not matching the results of the simulation. I thought it might be a units thing, but my dimensional analysis completely checks out to V - V = V.
https://preview.redd.it/edd4fz2twxp61.jpg?width=1024&format=pjpg&auto=webp&s=bf4a240efc70fee362816a5b932f204355618506
how do we determine this? would a photon with lower energy be more likely to get absorbed?
I was given that BE= hv-KE. why is this true? Is there a derivation that gets me here?
Hi!
I'm currently working on a lab about this and I feel pretty confused about what's going on. I'm supposed to use a simulation in any way I want (I can change the current, intensity, etc.) to find the threshold wavelength of sodium. I know all the basic equations for this, I just have no idea how to even go about solving this.
Could someone please point me in the right direction?
The classical physics failed to interpret the photoelectric effect. There is no time delay between the arrival of the radiation and the ejection of electron, but classical Physics says the opposite, so why Classical Physics saying this? Why the time delaying should be exist in the classical physics interpretation?
Does current not equal the speed at which the charge moves? is kinetic energy not also proportional to the particle's velocity as well? perhaps the answer is very obvious, but I have one of the COVID variants and it's frankly shitty and has made my brain operate at a suboptimal level. thanks a bunch to anyone who responds!
edit: is it because increasing light intensity basically means that there are more electrons emitted per unit of time? that would change the charges flowing per unit time but not the kinetic energy within each individual charge.
According to these articles Photoelectric effect can occur, however my books and my friend who is physicist say no is possible. Maybe i am misunderstanding :(, can help me?
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&cad=rja&uact=8&ved=2ahUKEwiHscGmucfuAhXVHbkGHdTFDxkQFjAGegQIFhAC&url=https%3A%2F%2Fresearchportal.helsinki.fi%2Ffiles%2F67904738%2Fnjp7_10_368.pdf&usg=AOvVaw3FkdfuV6ipUct6eoYvzVPi
https://journals.aps.org/pr/abstract/10.1103/PhysRev.128.2225
Why doesn't the Photoelectric Effect [work] before light reaches threshold frequency?
*messed up the title*
I just started learning the photoelectric effect so bear with me. I know that for an electron to be released, it needs to receive a certain amount of energy from light.
I read this online...
>Light below a certain threshold frequency, no matter how intense, will not cause any electrons to be emitted.
How come no electrons are released at all? Over time, won't the light provide enough energy to the electrons for them to be released?
The following point is given in my book:
>Very few photons( <1%), whose energy is greater than the work function, are capable of ejecting the photoelectrons.
So, does this mean that there are other factors that must be taken into consideration to conclude if the electrons will leave the surface? Or does a photon having energy > work function guarantee the ejection of an electron from the metal surface?
Edit:
Also, why is it that the chances of inner shell electrons being ejected increases once the energy of the incident light is more than the binding energy of the inner electrons.
Like, when the energy of the incident light is less than that of the inner shell electrons but more than that of the valence electrons, only the valence electrons are ejected. But if we incident a light that has more energy than the binding energy of the inner shell electrons, then more inner shell electrons are ejected than the valence shell electrons. Why is it so?
How does photoelectric effect contradicts classical physics ?
