Optics B/C

Froggie
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Re: Optics B/C

Post by Froggie »

dmackSD wrote:In Optics C, is there any requirement for whether the midline mirror is on the front (laser side) or back (target side) of the barrier? We are finding a solution if it is on the back is extremely difficult. Thanks!
Nope, no requirement, as far as I know.
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Re: Optics B/C

Post by jkang »

Hey all, UT Invitational just finished this past weekend so I'm here again with my test.

Optics Key
Optics Test

Some notes:
1. I wrote this at like 3am, please forgive me if the questions aren't that great :(
2. Almost all questions were pulled from Wikipedia, in either pages directly listed as topics by the rules or sublinks.
3. A few of these questions were from my college level waves lab. Considering the nature of the course, I'm sure that some achieving high schoolers and middle schoolers can confidently answer them with the right practice material.
4. Again as usual, if anyone has questions about the key or test please feel free to email me. I tried doing my best in explaining my answers in the key, but there could always be other questions.
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Re: Optics B/C

Post by WhatScience? »

jkang wrote:Hey all, UT Invitational just finished this past weekend so I'm here again with my test.

Optics Key
Optics Test

Some notes:
1. I wrote this at like 3am, please forgive me if the questions aren't that great :(
2. Almost all questions were pulled from Wikipedia, in either pages directly listed as topics by the rules or sublinks.
3. A few of these questions were from my college level waves lab. Considering the nature of the course, I'm sure that some achieving high schoolers and middle schoolers can confidently answer them with the right practice material.
4. Again as usual, if anyone has questions about the key or test please feel free to email me. I tried doing my best in explaining my answers in the key, but there could always be other questions.
This seems to be a good test. Thanks for this man.
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Re: Optics B/C

Post by 5uper5tring »

WhatScience? wrote:
jkang wrote:Hey all, UT Invitational just finished this past weekend so I'm here again with my test.

Optics Key
Optics Test

Some notes:
1. I wrote this at like 3am, please forgive me if the questions aren't that great :(
2. Almost all questions were pulled from Wikipedia, in either pages directly listed as topics by the rules or sublinks.
3. A few of these questions were from my college level waves lab. Considering the nature of the course, I'm sure that some achieving high schoolers and middle schoolers can confidently answer them with the right practice material.
4. Again as usual, if anyone has questions about the key or test please feel free to email me. I tried doing my best in explaining my answers in the key, but there could always be other questions.
This seems to be a good test. Thanks for this man.
Question 2: A ​ ​plane ​ ​mirror ​ ​can ​ ​form ​ ​real ​ ​images ​ ​of ​ ​what ​ ​types ​ ​of ​ ​objects?

I see that Wikipedia page on Plane Mirror (https://en.wikipedia.org/wiki/Plane_mirror) has the following sentence: "Virtual objects produce real images, however.[citation needed] The focal length of a plane mirror is infinity;[4] its optical power is zero."

What exactly is a "virtual" object in this context?
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Re: Optics B/C

Post by 5uper5tring »

5uper5tring wrote:
WhatScience? wrote:
jkang wrote:Hey all, UT Invitational just finished this past weekend so I'm here again with my test.

Optics Key
Optics Test

Some notes:
1. I wrote this at like 3am, please forgive me if the questions aren't that great :(
2. Almost all questions were pulled from Wikipedia, in either pages directly listed as topics by the rules or sublinks.
3. A few of these questions were from my college level waves lab. Considering the nature of the course, I'm sure that some achieving high schoolers and middle schoolers can confidently answer them with the right practice material.
4. Again as usual, if anyone has questions about the key or test please feel free to email me. I tried doing my best in explaining my answers in the key, but there could always be other questions.
This seems to be a good test. Thanks for this man.
Question 2: A ​ ​plane ​ ​mirror ​ ​can ​ ​form ​ ​real ​ ​images ​ ​of ​ ​what ​ ​types ​ ​of ​ ​objects?

I see that Wikipedia page on Plane Mirror (https://en.wikipedia.org/wiki/Plane_mirror) has the following sentence: "Virtual objects produce real images, however.[citation needed] The focal length of a plane mirror is infinity;[4] its optical power is zero."

What exactly is a "virtual" object in this context?
Never mind. I found the answer. Tricky question
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Re: Optics B/C

Post by mnparhy »

Rulebook says "Participant tools/templates may remain on the LSS during this process".

Chalker, could you please confirm that during laser shoot and recording result, participant can keep the template on LSS board, if they want? Or is this left to event supervisor's discretion? Last year, this part of rule was exactly same, but our team were asked to take the templates out before laser shoot.

Thanks.
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Re: Optics B/C

Post by Unome »

mnparhy wrote:Rulebook says "Participant tools/templates may remain on the LSS during this process".

Chalker, could you please confirm that during laser shoot and recording result, participant can keep the template on LSS board, if they want? Or is this left to event supervisor's discretion? Last year, this part of rule was exactly same, but our team were asked to take the templates out before laser shoot.

Thanks.
Said event supervisor was likely mistaken (though as always, hard to say for certain without being there).
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Opinions expressed on this site are not official; the only place for official rules changes and FAQs is soinc.org.
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Re: Optics B/C

Post by chalker »

Unome wrote:
mnparhy wrote:Rulebook says "Participant tools/templates may remain on the LSS during this process".

Chalker, could you please confirm that during laser shoot and recording result, participant can keep the template on LSS board, if they want? Or is this left to event supervisor's discretion? Last year, this part of rule was exactly same, but our team were asked to take the templates out before laser shoot.

Thanks.
Said event supervisor was likely mistaken (though as always, hard to say for certain without being there).
This is why I always recommend taking a copy of the rules with you to an event.

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Re: LSS Retrofit Instructions (strawman)

Post by SVSciOly »

PHXcoach wrote:Thank you for the suggestions.
Comments below:
3. The biggest challenge I've found (and hence the delay in producing an official document like this) is cutting the metal sheet. You can buy metal sheets at Lowes / Home Depot anywhere in the country, but cutting it down to size is challenging. You didn't really speak to that part, so I'm curious if you have any advice on it
I had the same concern about the metal sheet because I was worried that trying to cut it with a saw might bend it - When I put in the document text "Your local metal supplier is probably the best source for the sheet metal because they can also shear it to size, otherwise a local metal workshop may be able to oblige." I was thinking of a professional metal supplier like Industrial Metal Supply Co, rather than a home improvement store.

If you did decide to use a saw then using a plywood backing support on one or both sides of the metal sheet might help keep it flat.
4. Would you mind me using this document as the base for the official LSS retrofit document we need to post on the soinc.org website? The main changes I'd make relate to the previous 3 bullets.
Feel free - that is why I shared the document in a source format rather than as a PDF.

I will be interested to see what ideas and solutions other people have come up with.

I am going to build a new LSS today and update my others, but I found magnetic paint at Home Depot (https://www.homedepot.com/p/Rust-Oleum- ... /202351175) and am just going to try and use that instead of the metal sheet. This might be a good idea for those that don't want to cut metal, or already have a LSS as they just have to paint the bottom surface. I don't know how magnetic the paint is, but I will let you know after I build it. The document had lots of good tips though & thanks for making it.
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LSS: how to get the correct angle of the laser reflection

Post by home2mars »

Hi all,


After days of trying and getting really frustrated, maybe this forum can help. I have not used the box yet. So the setup is just on the table.
The table is as level as I can make it. I have printed the protractor templates (from document I found ___ forgot exactly, but the title is "Setting up for the Laser Shoot.docx"
I also use graph strips.

I angle the first mirror 45o using the protractor template above (location: on the middle line, about 2 inches in front of the laser)
Then using the graph strips to find where the laser reflection should be and then place a second mirror there.

As simple as that. BUT for the life of me, for days I can not even get the laser beam to correctly fall in the middle of the second mirror.
It is always off by 3-4 millimeter and that is enough to create big enough error that I can not even hit the third mirror.

Anything I do wrong? How to accurately angle the mirror(s) and then getting a correct angle to position the "catching" mirror.

Thanks!

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