[The Fifteenth Blog] Quantum Physics.

I realize that I made a ridiculously stupid mistake on the physics test today. Rah. How frustrating. >_< And more sad news (or not, haha): this will be my last physics blog post. Aww... :[

     I don’t really know how to relate quantum physics to everyday life, though, except by likening the photoelectric effect to photosynthesis, which is quite important in our lives, I'd say (biology and physics in one post?!? o_O). And of course I don't really know anything about photosynthesis anymore because I don’t even remember what I (should have) learned yesterday, let alone information from 9^th grade biology. So let’s get cracking.

     The photoelectric effect is the ejection of electrons due to light striking a material. An increase in light intensity results in more electrons being released because more intense light => more photons => more electrons emitted. However, the light must be greater than a certain frequency, otherwise no electrons will be emitted at all, regardless of the intensity, since low frequency => less energetic photons => not enough energy to free electrons. An equation we can relate to the photoelectric effect is E = KE + ø, where E is the energy of the photon (also equal to hf), KE is the kinetic energy of the released electrons (0.5mv²), and ø is the work function of the material (the minimum amount of energy needed for an electron to be ejected from it). 

     Photosynthesis is like the photoelectric effect because in both cases, light striking a material results in the emission of electrons. When sunlight shines on a plant, chlorophyll molecules absorb it and they become excited, releasing electrons. (Some complicated processes occur here to transport electrons...).  And by the end, the electrons have been converted to ATP, and photosynthesis has successfully converted light into sugar. :]