Reading Quiz

Question 1:

Answer:

1. why do you only see certain colors when looking at the different gases?
2. I feel okay with all that we have covered in class.
3. The stuff on polarization is still a little frustrating.
4. nothing at this time
5. I understand everything so far this week.
6. n/a
8. none
9. i understand most of the material
10. I understand everything so far.
11. --
13. None.
14. None.
15. ---
16. Nothing, thanks.
17. I think I am okay with previous material.
18. N/A
19. Can we talk about the constructive and destructive interference discussed in the sunlight section?

Question 2:

Answer:

1. Spontaneous emission of radiation is unpredictable and independent. Stimulated emission of radiation occurs when an excited atom duplicates a passing photon. The photon that is emitted is exactly like the stimulated photon.
2. The main difference between spontaneous and stimulated emission of radiation is that spontaneous is light that is independent and unpredictable in character (emitted by hot objects or by individual electrons in an electrical discharge) and stimulated occurs when an excited atom can emit a duplicate photon on its own (lasers).
3. Spontaneous emission is when photons are emitted independently of each other and is unpredictable while simulated emission is when the photons copy each other in a way that they travel in perfectly the same way.
4. spontaneous-each particle of normal light is emitted willy-nilly stimulated-light created when an excited atom or atomlike system duplicates a passing photon.
5. Spontaneous emission happens without regard to other photons surrounding it. Stimulated emission is caused when an excited atom duplicates a passing photon, and these photons form an electromagnetic wave.
6. Spontaneous emission of radiation is when an atom, in an excited state, might or might not emit a photon. It is unpredictable, and that photon might go off in any direction. However, in stimulated emission, an excited atom can be made to produce an exact type of photon by having another photon passed through it at the right wavelength. As a result, it will produce an identical photon.
7. spontaneous emission consists of photons that are emitted but have no relationship to each other. Stimulated emission is when an excited atom emits photons that are copies of each other so there is only a single electromagnetic wave.
8. Light particles are unrelated in spontaneous emission and exact duplicates of one single photon in stimulated emission.
9. Spontaneous emission of radiation is when each photon of is emitted without any relationship to the other light particles being emitted near by. Stimulated emission of radiation is when a photon emitts another photon that creates the exact same electromagnetic wave.
10. Spontaneous emission is completely random and independent of other excited atoms, while stimulated is due to a passing photon and acts like a duplicate.
11. Spontaneous emission of radiation is how normal light is created, and each photon of light is emitted without any relationship to the other photons around it, so the light has an independent and spontaneous nature to it. Stimulated emission of radiation is purposefully created when an excited atom duplicates a passing photon. The excited atom emits the duplicate photon, and the two are almost indistinguishable, creating one electromagnetic wave. Spontaneous emission results in incoherent light whereas stimulated emission results in coherent light.
12. Spontaneous radiation comes from noram light and each photon in the light is emitted randomly? --- the photon's orientation is not connected to the orientation of the other photons. In stimulated radiation, a single photon is duplicated many times until you have a single electro magnetic wave made of many photons, all traveling exactly the same.
13. The main difference between these two types of emission of radiation is that the particles of spontaneous light are emitted without having any relationship to other nearby light particles being emitted. Stimulated light, however, is created when an excited atom duplicates a nearby photon, producing two perfect copies that form and electromagnetic wave.
14. The main difference between these two types of emission of radiation is that the particles of spontaneous light are emitted without having any relationship to other nearby light particles being emitted. Stimulated light, however, is created when an excited atom duplicates a nearby photon, producing two perfect copies that form and electromagnetic wave.
15. Spontaneous emission of radiation is photons created independent of other light particles, while stimulated emission of radiation creates a dupilcate identical photon of the atom passing through.
16. Spontaneous emission of radiation travels in disordered multidirectional waves while stimulated emission of radiation forms ordered waves.
17. In spontaneous emission of radiation the system releases stored energy randomly and the photon that results is independent and unique. In stimulated emission the system releases stored energy by duplicating a photon passing through that system. Spontaneous emission produces incoherent light and stimulated emission produces coherent light.
18. The main difference between spontaneous emission of radiation and stimulated emission of radiation is that spontaneous emission of radiation is unpredictable, whereas stimulated emission of radiation can occur only when the excited atom is capable of emitting the duplicate phoon spontanwously.
19. Spontaneous emission of radiation is created by spontaneous light, which is unpredictable and independent of other light particles emitted nearby. Stimulated emission of radiation is created by an excited atom emitting duplicates of a passing photon. In spontaneous emission of radiation, photons are created independently whereas stimulate emission of radiated photons are identical to one another in every way since they are duplicates.

Question 3:

Answer:

1. Coherent light is special because all of the light particles are completely identical and form a single electromagnetic wave. Since all the photons are identical, they can focus together at a smalll spot like in a laser.
2. Coherent light is special because it consists of many photons which are identical, and they form just one electromagnetic wave. Coherent light is useful as a result of it being a single wave, so it exhibits very clearly the effects of interference. (Easily seen in the coherent light emitted by lasers.)
3. Coherent light is special because all of the light particles are absolutely identical and form one single electromagnetic wave. Coherent light is useful to make lasers.
4. Light consisting of many identical photons and a singleelectromagnetic wave. It exhibits remarkable interference effets.
5. Coherent light consists of many identical photons and a single electromagnetic wave. Because it has just this single wave, it has interesting interference effects. The light can also be focused on a very small spot, so it is useful in laser printers.
6. Usually light is incoherent, its electric field varies depending on the direction of each individual photon, so its hard to pin down any one field. Coherent light, on the other hand, makes sure all the photons are moving the same way so that they have the same orientation.
7. The atoms acceleration is not in random directions so the waves are not at different wavelengths or moving in different directions. Coherent light is from a light wave created by identical photons.
8. Coherent light combines many identical photons in a single electromagnetic wave. Coherent light can produce an extremely focused beam and can be used when precision is necessary.
9. Coherent light is when many identical photons create a single identical electromagnetic wave.
10. Coherent light can be focused down to a very small beam because it is a single electromagnetic field caused by it. It's useful because it eliminates the random other emf's and can therefore be focused to a small area or very sensitive task, like reading from only one area on a cd.
11. Coherent light is composed of identical light particles that form a single electromagnetic wave. This kind of light is useful because it is able to exhibit remarkable interference effects. It is also fairly easy to amplify the light using a laser oscillator and laser medium.
12. Coherent light is made of stimulated radiation, and has many photons in a single electromagnetic wave. This light is the type used for lasers
13. Coherent light is special because it's made up of many such perfect copies of photons, and therefore one electromagnetic wave. Stimulated emission and the production of coherent light first made light amplification possible, resulting in intense beams of light known as lasers.
14. Coherent light is special because it's made up of many such perfect copies of photons, and therefore one electromagnetic wave. Stimulated emission and the production of coherent light first made light amplification possible, resulting in intense beams of light known as lasers.
15. Coherent light consists of identical photons that create a single electromagnetic wave. This wave only needs one electron to pass through an excited system to dupilcate it endlessly.
16. Coherent light has remarkable interference effects.
17. Photons of coherent light are identical to one another in every way and form a single electromagnetic wave. Coherent light has very good interference effects. This is used in lasers.
18. Cohoerent light is light conssisting of many identical photons and a sinle electromagnetic wave. It is useful because it exhibits remarkable interference effects, these effects are easily seen in the coherent light emitted by lasers.
19. Coherent light is special because it is made of many duplicated, identical photons proucing a single electromagnetic wave. This is useful because identical photons can focus together to an extremely small spot, wheras independent photons might not end together at the focus of a lens.

Question 4:

Answer:

1. In a LED, the electrons in the conduction level in the ptype anode jump to the empty valence levels. When this happens they undergo radioactive transistions and emit light.
2. An LED emits light when conduction level electrons in the p-type anode of a diode frequently undergo radiative transistions to empty valence levels.
3. Current flows from the anode to the cathode and electrons in the conduction level in the n-type cathode travel across the p-n junction to change to an excited state in the p-type anode. Theen conduction level electrons in the p-type anode undergo radiative transitions to empty valence levels and by thus emit light.
4. Must be forward biased with a voltage drop of at least 1.9 V. The current carying diode uses that voltage drop to inject electrons into the anode's conduction band where they have energies 1.9eV above valence band. Many electrons then release their excess energies as photons of light.
5. The conduction level electrons in the p-type anode undergo radiative transitions so they can empty their valence electrons, thereby discharging energy and creating light.
6. An LED produces light by the electrons move from one side of the p-n junction down to the other. Since they are dropping in their energy level, they release a photon which we can see.
7. Electrons cross the diode's p-n junction into the anode's conduction levels and undergo radiative transitions to the empty valence levels.
8. An LED lights up when electrons undergo radiative transitions to empty valance levels after passing the p-n junction. Current can only flow through in one direction (as in any diode), and the band gap determines what color light is produced.
9. conduction level electrons in the p-type anode undergo radiative transition sto empty valence levels and transmit light when they do.
10. This is the one thing i'm not totally sure about. If I understood this correctly the light is caused by electrons shifting to empty valence levels in a p-type anode conductor.
11. I had trouble with this part, but what I gather from it is that LEDs emit light when electrons shift from a conduction level to a valence level, and the color of that depends of how much energy is released during this process. The shorter the wavelength is of the light, the more energy is required. I'm not sure how the voltage drops factor in.
12. I was kind of confused by this. it sounds like the current passing though the LED causes valence electrons to jump to higher levels and emit light
13. I found this section of the reading confusing and I'd like to spend some time talking about it.
14. I found this section of the reading confusing and I'd like to spend some time talking about it.
15. Light is emitted in a LED when electrons that have crossed the diode's p-n junction into the anode's conduction levels undergo radiative transitions to the empty valence levels.
16. It is made up of a diode and in the specilized diode in the p-type side conduction electrons frequently undergo radiative transitions to empty valance levels and this emits light.
17. In an LED, light is emitted when electrons that have crossed the diode's p-n junction into the anode's conduction levels undergo radiative transistions to the empty valence levels. The color of light produced by the LED is determined primarily by the anode's band gap.
18. A LED emits light by having electrons release energy as it shifts from a conduction level to a calence level and can produce a photon.
19. When electrons have crossed a diode's p-n junction into the anode's conduction level and then undergo radiative transitions to the empty valence levels, this emits light.

Question 5:

Answer:

1. nothing. this section was relatively clear compared to other sections.
2. I wasn't confused by this section of the text.
3. Does spontaneous emission cause incoherent light and simulated emission cause coherent light?
4. i'm confused on laser amplifiers and oscillation.
5. I didn't understand how laser amplification works with the mirrors.
6. I don't quite understand LEDs.
8. I was confused by the explanation of how lasers duplicate photons and the section on how a laser medium works.
9. i understand most of the material in this chapter
10. I think I understood all of this.
11. I found the whole section on LEDs and diodes to be confusing. I also had trouble with population inversion.
12. LEDs
13. See above.
14. See above.
15. ---
16. How an LED emits light.
17. I was very confused actually on the last question, I found the answer, but I do not understand it really at all. Also, the idea of stimulated vs. spontaneous emission was also a little confusing.
18. I was confused about the concepts of the LED lights and how they light up and also how a laser works.
19. I would like to go over how lasers work- population inversion and how the p-n junction and valence levels in this case differ from what we have previously talked about.