Optics B/C

[dmackSD]

I took our box from last year to our local Sheet metal store and got a very nice plate custom cut for a $6.09 out the door. Worth the trip rather than trying to cut one ourselves! Figure we will practice magnetized with the magnets down and non'magnetized with the mirror upside down.

[SawnEcho]

Can you touch the barrier as long as you don't move it? Will the barrier or mirrors have magnets on the bottom? What will happen if you move the barrier (how many points will be deducted) ? What do they consider as moving the barrier? By an inch or a centimeter?

[Froggie]

Can you touch the barrier as long as you don't move it? Will the barrier or mirrors have magnets on the bottom? What will happen if you move the barrier (how many points will be deducted) ? What do they consider as moving the barrier? By an inch or a centimeter?

1. It'll probably depend on the proctor (I think). Some proctors tape down the barrier, so in that case touching it should be okay.
2. It's not required, but some might.
3. I don't know. In some cases, you could get a 0 for the laser shoot part I think.
4. Again, depends on the proctor.

Once at states my partner knocked the barrier over completely but they let us proceed.

[jajefan]

The ES can place it at any angle. It can be at 90 or 45 or 3.141592 (theoretically) degrees.
I don't think they'll tell you, but some might.
Check out the rules.

Sorry, I thought rule 3.j was ambiguous as to whether or not nonperpendicular angles referred only to the midline barrier or to the other barriers as well. Thanks for clarifying.

[Pettywap]

Hellloooooooo,
For Div. B, is it necessary to know the percentage of reflection in a refractive problem? (in refraction part of the incident ray, part of it is reflected). Basically do we need to know the percentage that is reflected. (sorry if this is very confusing). I JUST NEED TO KNOW!!!!!

[John Richardsim]

Hellloooooooo,
For Div. B, is it necessary to know the percentage of reflection in a refractive problem? (in refraction part of the incident ray, part of it is reflected). Basically do we need to know the percentage that is reflected. (sorry if this is very confusing). I JUST NEED TO KNOW!!!!! ;) ;) ;) ;) ;) ;) ;)

If I'm not mistaken, the reflectance of a surface is calculated using the Fresnel equations, which would be rather tedious to use in a question. The only manner in which this sort of topic has been asked on a test that I've seen is the special cases of total internal reflection and Brewster's angle.

[keklord88]

Does anyone know if we're allowed to use other tools to measure the angle besides just a simple protractor? (eg. digital angle gauge)
And what about a tape measure instead of a clunky ruler?

[Jdoglloyd]

Does anyone know if we're allowed to use other tools to measure the angle besides just a simple protractor? (eg. digital angle gauge)
And what about a tape measure instead of a clunky ruler?

Wouldn't a tape measure be clunkier? With the metal casing and all

[keklord88]

Does anyone know if we're allowed to use other tools to measure the angle besides just a simple protractor? (eg. digital angle gauge)
And what about a tape measure instead of a clunky ruler?

Wouldn't a tape measure be clunkier? With the metal casing and all

The tape can be bent so you would make a "L" shape with the tape measure so that the casing would be out of the way. This way you can measure in tight spaces that you otherwise coudn't with an inflexible ruler. Horrible drawing showing what I mean:

[Adi1008]

Does anyone know if we're allowed to use other tools to measure the angle besides just a simple protractor? (eg. digital angle gauge)
And what about a tape measure instead of a clunky ruler?

Wouldn't a tape measure be clunkier? With the metal casing and all

The tape can be bent so you would make a "L" shape with the tape measure so that the casing would be out of the way. This way you can measure in tight spaces that you otherwise coudn't with an inflexible ruler. Horrible drawing showing what I mean:

You could also just use smaller rulers

I think tape measures are allowed (rule 2.b) since it counts as "any measuring tool"