did you get your engineering degree?

+Maddix I know!!! I felt so confused in lecture and now I'm like "That's it? SIMPLE!"

Christy N and you are Australian

Did you pass your Alevels?

re: "wave/particle duality." It would be nice if you could "clear up" this constant reference to a light as a 'particle' as it REALLY clouds the understanding of EM (electromagnetic) radiation at _low_ frequencies (compared to light) such as demonstrated here at 9 GHz and a little further on at 140 MHz in this MIT video: kzfaq.info/get/bejne/ra6FYLd6v9yuhH0.html

maffak321 I definitely lol'd too When he said that

yijing Yao Yay! Thanks!

Ali Marafi One thousand thumbs up! Well, not for your uncle.

for exploding himself?

Chirag Raju Great idea!

Can't wait :)

I'm so sorry! We have many classes in the US that emphasize memory over understanding, too. I agree that understanding is infinitely better.

Abdullah Rushdi I guess I could put the ammeter anywhere on this series circuit, and it would read the same current. I use Walker's intro textbook, and this is his circuit sketch. You've still got light hitting the same side, right?

Doc Schuster no that is the issue... i have light hitting the straight side and the curved one is the collector.

Abdullah Rushdi ...but is the battery facing the other direction?

Positive side of the battery at the straight electrode which is, in my book, the emitter. The negative side at the curved electrode which is the collector. This is Alevel physics syllabus. Edexcel book made by Patrick fullick

Japjee Kaur, well in any atom, electrons exist in several orbitals and they don't have the same energy, it's the same here

The best way I can describe of "lights", it seems everything have 'equilibrium'.

Neeraj Khadagade It's microamps. It's actually pretty hard to measure, but you can put it into a little 741 wired up as a current amplifier. It's a worthy experiment to build if you can get your hands on an old photoelectric tube.

Doc Schuster Alright! Thanks!

I can put them into a spectrometer. A diffraction grating or prism and a photocell is all we really need.

Sally Milson I have also noticed that I can't reply to about 25% of comments. Have any idea why? Good answer, BTW.

Doc Schuster it's probably a google+ thing if I had to guess

Sally Milson DANG IT, GOOGLE PLUS! MUST YOU RUIN EVERYTHING I'VE BEEN WORKING SO HARD TO CREATE?

Sally Milson Sally, I think you're very close. I was just reading about this. The model whereby we imagine many free electrons / a "sea" of electrons / a conduction layer doesn't fit with the photoelectric effect. When an electron is ejected from the surface, there's a clear gain in momentum. For momentum to be conserved, there must be an equal gain in momentum in the opposite direction. The photon can't provide this momentum gain because (a) its momentum is negligible, and (b) it disappears / is absorbed. The lattice structure, then, must recoil when the electron is ejected. In order to assert that the lattice / proton structure is what recoils, we must imagine the electron as bound to a nucleus in a specific energy level--as a valence electron, as you correctly say. (The conduction band/sea of electrons is built from the "overlapping/mixing" of valence energy states in the many neighboring atoms that are bonded together to form the solid metal.) www.virginia.edu/ep/SurfaceScience/PEE.html

I'm glad I can help! Keep rocking.

As far as I understand it. The Beam of the Light must be strong enough to split (Jump Ship).

Frequency = Radiation

Molecule can split light or absorb, yes. NOTE: It seems everything have 'equilibrium'.

YES, your understanding of it is how I understood of "lights". It seems everything have 'equilibrium'.

It seems "Light" is Electro + Magnetic + Wave. Here is how I see it.... Electro = Electric - Photons + Magnetic = +/- & + Wave = Radiation. If you put it all together, that is how its able to travel and radiate and travel fast too due to wave.

I'm glad you liked it!

Apoorva Joshi they go honeymoon

They cease to exist, they are "absorbed" by the ejected electrons, which now contain the photon's energy.

Since a photon is only energy the energy gets transferred to the electrons in form of the kinetic energy

Kay Wu 1) You're thinking of light as a wave, but it's a stream particles. 2) kinetic energy of the fastest electrons is converted into electric potential energy. Do you know the equation for the EPE for a charge at a voltage?

Doc Schuster 1) I've always imagined light as both - a stream of particles that travel in a wave. Is it incorrect to think of it like that? 2) Ah, no, I do not. I'll look into it. Thank you so much for taking the time to reply!

Kay Wu Yes - wave packets. But you can't define an amplitude of the "wave" The photoelectric effect is super-duper quantum.

Kay Wu The intensity of the light beam can be thought of as the "density" of the photons. More specifically, the intensity of the light beam (upon reaching the metal surface) indicates the number of photons striking a square meter per second. This can be illustrated through equations: E_one photon = hf E_many photons = (number of photons) x (hf) P_many photons reaching the metal = (number of photons) x (hf) / t intensity of light at the metal surface = P / A intensity = (n / t) x (hf / A) This is a quantum mechanical interpretation of "light intensity." There is also a classical interpretation of wave intensity, which you've pointed to. Here's the classical interpretation: 'the intensity of a wave is proportional to the amplitude of the wave squared.' This classical interpretation of intensity can be useful in cases/experiments where light exhibits wave behaviors (like diffraction and interference). However, the classical interpretation of intensity (as related to amplitude) is out of place in the particular case of photoelectric effect, since in this effect, light exhibits particle behaviors rather than wave behaviors.

Dan Hillman Oh, that would be awesome. I have gotten mine from salvage inside old 1950's and 1960's spectrophotometers. Good luck!

Similar idea! The photoelectric effect and the photovoltaic effect (of diodes) have a lot in common. Rectifiers served the electronic purpose of diodes before the latter were formally discovered. Interestingly, crystal rectifiers were the FIRST recs used in radio, and they WERE diodes, but no one knew why they worked. Cool.

From my understanding of it, yes. It seems everything have 'equilibrium'.