Optics B/C

[antoine_ego]

Just for clarification, when the rules state

All reference materials to be used during all parts of the competition must be initially secured within a 3 ring binder...

does this include materials used for the laser shoot?

[Unome]

Just for clarification, when the rules state

All reference materials to be used during all parts of the competition must be initially secured within a 3 ring binder...

does this include materials used for the laser shoot?

When I competed in Simple Machines this was usually the case (although we didn't really need much reference materials for the lever).

[jasony123123]

On the rules there is no restriction on where along the midline the barrier can be placed. So does that mean the proctor can put the barrier 1 cm away from the laser; or will the placement still be relatively reasonable?

[chalker]

On the rules there is no restriction on where along the midline the barrier can be placed. So does that mean the proctor can put the barrier 1 cm away from the laser; or will the placement still be relatively reasonable?

Well if the barrier is 1cm away from the laser, will ANYBODY be able to get a mirror in there and deflect the beam away? No, hence the supervisor has to allow enough room to put a mirror in there.

[jkang]

Here's my optics test from the recent UT-Austin invitational (key). If you have any questions about it, feel free to PM or email me!

[jasony123123]

Do you think we will need to know the Lensmakers equation

[Fluorine]

Do you think we will need to know the Lensmakers equation

In the rules manual it say under section d.v "Division C also lensmaker's equation." So if you are C division 100% yes you should know lensmakers.

[svora]

Are we allowed cheat sheets in the written test part of the Optics B event ? If yes, what are the dimensions ?

[Unome]

Are we allowed cheat sheets in the written test part of the Optics B event ? If yes, what are the dimensions ?

This is the type of question that can be easily answered by reading the rules. Your coach should have received a copy of the rules when they registered your school's team with the state organization; you can also buy a physical copy yourself ($8 plus shipping) or get the mobile rules app (Apple/Android, $4). Reading the rules thoroughly should always be the first thing you do for any new event.

[Cloudia]

Hello

This is my first year coaching optics C. My experience with SciOly is with Robotic Arm previously, so I'm new to the theory side of events. My students and I covered all of the non-state/national level theory before they competed in the Cornell Invitational in NY this past weekend.

While I was expecting that my students would struggle with the state/national level theory (lasers, multiple lenses, etc) that the Cornell Invitational is known for, there were questions in which I can't see how they fit within any of this year's optics topics. Alternatively, is it common to see more topics thrown than expected?

I'm hoping that someone may be able to provide me with guidance on whether I need to be teaching this extra material?

For completeness, I'll copy as much of the relevant questions as possible to maintain the context.

So that these questions don't scare students as they did my own, all of the other questions were the type we expected from the optics C rules. These are just the tricky exceptions.

Thank you in advance for any advice that can be offered!

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Question 24. Diagrams are shown for both absorption (first) and emission spectra (second). Differentiate between the two spectra and explain how the second spectrum is produced.

(I have taught absorption spectra, but not emission, and especially not how it's created. Is this required knowledge?)

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Question 25. What is Huygens principle, and how does it relate to the double-slit experiment (assume the width of the slit is less than the wavelength of course)? Again feel free to use drawings as aids to explain.

(I'm not sure which topic this comes under this year?)

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Question 26. Analysis of hydrogen spectral lines from a distant star are measured to have a wavelength of .21107m. However, hydrogen emission lines are measured to be .21106m in a vacuum. How fast is the star travelling in terms of the speed of light (c)? Is this an example of red shift or blue shift?

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Question 27. Give an example of when light acts as a particle, and an example of when it acts like a wave.

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Question 39. A hydrogen electron transitions from n=3 to n=1. Is a photon absorbed or emitted?

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Question 40. What is the photon's energy in eV?

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Question 41. What is the frequency of the photon?

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Question 9. Give the speed of light in each medium, relative to c, the speed of light in a vacuum. Also give the wavelength and frequency light in each medium. Also give the energy of a single photon in each medium. Find the values for all three media (including the initial medium). Assume that the initial wavelength is 635nm.

(Diagram was light entering air and then two mediums with different refractive indexes. My question is whether the photon energy component should be included in this year's material?)

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Question 10. Take the energy values from number 9. Explain any pattern or lack or pattern in the values. Why does this occur?