Optics B/C

[WStevens2090]

Hey guys, I haven't done this event since 6th grade and was wondering what textbook you would suggest to study this event out of?

Thanks

[SPP SciO]

Hey guys, I haven't done this event since 6th grade and was wondering what textbook you would suggest to study this event out of?

Thanks

Start here http://www.physicsclassroom.com/class and check out the Reflection & Refraction lessons at the end. For division B at least, any high school physics textbook would probably have more than enough information and practice problems to keep you busy for a while. Of course, the rules specify other topics (e.g., optical instruments, the human eye) that you may want to seek more specialized resources to help you learn.

[maxxxxx]

Does anyone know where to buy mirrors to make our own set-up? My google search power is failing.

[Fluorine]

Does anyone know where to buy mirrors to make our own set-up? My google search power is failing.

Hobby Lobby has them for sure. Also when your searching look for craft mirrors.

[chalker]

Does anyone know where to buy mirrors to make our own set-up? My google search power is failing.

Hobby Lobby has them for sure. Also when your searching look for craft mirrors.

Pretty much any craft store: JoAnns, Michaels, Hobby Lobby, etc.

[Unome]

How similar is this year's LSS to the 2012 version? (is this still applicable?)

[chalker]

How similar is this year's LSS to the 2012 version? (is this still applicable?)

The LSS is identical. That document is absolutely still applicable. The only significant change is the addition of a mirror to one of the barriers.

[sciencekid7]

Some questions about Optics B.

If the barrier is kept right up to the laser, obviously we cannot have a laser shoot since we need room between the laser and the barrier to position any mirrors as needed. What is the minimum distance between the side of the box with the laser and the barrier mirror?

Similarly, if the barrier is kept right up to the ruler, we cannot reach the target if it is near the barrier. What is the minimum distance between the barrier and the ruler?

Can the barrier mirror be parallel to the center line? Can the barrier mirror face the ruler instead of the laser?

Are the competitors allowed to lift or move the barrier in order to position templates or measuring devices and then place the barrier back in the same location and orientation?

[SPP SciO]

Some questions about Optics B.

1. If the barrier is kept right up to the laser, obviously we cannot have a laser shoot since we need room between the laser and the barrier to position any mirrors as needed. What is the minimum distance between the side of the box with the laser and the barrier mirror?

2. Similarly, if the barrier is kept right up to the ruler, we cannot reach the target if it is near the barrier. What is the minimum distance between the barrier and the ruler?

3. Can the barrier mirror be parallel to the center line? Can the barrier mirror face the ruler instead of the laser?

4. Are the competitors allowed to lift or move the barrier in order to position templates or measuring devices and then place the barrier back in the same location and orientation?

My interpretation - I'm not an Optics pro but these are the relevant sections of the rules -

1, 2: Rule 3.c says "can be easily relocated anywhere in the LSS by the competitors." with regard to the mirrors. 3.h says "They must be fixed in the same position and orientation in the LSS for all teams." with regards to the barriers. So, I think that when the event supervisor sets the barrier, he or she would be free to glue them in place. However, they must take 3.c into account, and not place them so close to an edge as to exclude a mirror from being relocated there. Long story short, it will likely be reasonable.

3: Rule 3.g covers this - there will be one "somewhere along the midline to block the laser beam." Only in Div. C will there be 2 additional barriers; those barriers may well be "placed elsewhere" which certainly includes parallel to the midline. As far as the direction the mirror faces, "a mirror similar to the others attached to one side" does not specify, so it could be any direction.

4: 3.h - "Competitors must not adjust the mirror's position." Since the barrier in div. B will have the mirror, lifting or moving it would be considered an adjustment, so no. In div. C, it's not explicitly clear whether the other two barriers without the mirrors may be adjusted - however it's a safe bet to assume not, because the barriers "must be fixed in the same position" so I would treat them as if they were bolted into place.

[kenniky]

Does anyone have a good source for studying optical absorption spectra?