Optics B/C

[foreverphysics]

For div. B nerds out there, do you guys study stuff like the thin-lens equation and stuff??? I feel like I'm studying in too much detail...

For division B, you probably don't have to know the thin-lens equation, but I'd be familiar with the Gaussian Lens Formula.

I've never heard of Gaussian Lens Formula...but I do know all the thin lens stuff. Seems like we've been studying backwards.

[Infinity Flat]

The thin-lens equation is I/f + I/Do = I/Di right? (Just double checking here...)

i thought it was
1/do + 1/di = 1/f

Thats what i've been using.. 1/f=1/di plus 1/do

Sorry for any confusion. My book refers to that as the Gaussian lens equation and

(n-1)[1/R1 - 1/R2] = 1/do + 1/di

as the thin lens equation.

[JSGandora]

Sorry for any confusion. My book refers to that as the Gaussian lens equation and

(n-1)[1/R1 - 1/R2] = 1/do + 1/di

as the thin lens equation.

That is just the Lensmakers' Equation on the LHS which equates to 1/f.

The thin-lens equation is I/f + I/Do = I/Di right? (Just double checking here...)

i thought it was
1/do + 1/di = 1/f

Now this is the Gaussian form of the Thin-Lens equation just using different conventions.

For division B, you probably don't have to know the thin-lens equation, but I'd be familiar with the Gaussian Lens Formula.

Hm...they're the same. The Thin-Lens equation is the most basic formula in optics so it's good to know I would think.

[Infinity Flat]

Sorry for any confusion. My book refers to that as the Gaussian lens equation and

(n-1)[1/R1 - 1/R2] = 1/do + 1/di

as the thin lens equation.

That is just the Lensmakers' Equation on the LHS which equates to 1/f.

Yes, that's right.

I've never had to use the Lensmaker's Equation personally, but it's relatively simple, and you're allowed a binder, so it couldn't hurt to include it somewhere on a formula sheet.

[Platypus]

For the laser shoot, are we allowed to test with the templates under the mirrors? I want to know which way to practice before Regionals...

[hexagonaria]

For the laser shoot, are we allowed to test with the templates under the mirrors? I want to know which way to practice before Regionals...

Yes, you can put your templates down and place the mirrors on top, and you don't have to remove them when the laser is fired. Or at least the guy who did my laser shoot didn't make me remove them. I believe I brought up this topic a few pages back, you should check that out.

[Infinity Flat]

For the laser shoot, are we allowed to test with the templates under the mirrors? I want to know which way to practice before Regionals...

Yes, you can put your templates down and place the mirrors on top, and you don't have to remove them when the laser is fired. Or at least the guy who did my laser shoot didn't make me remove them. I believe I brought up this topic a few pages back, you should check that out.

You are correct here. However, you should NOT expect to be able to move the blocks, so your template will have to fit around them.

[cngu23]

For the laser shoot, is there a defined size for the obstacles?

[JSGandora]

Yes, if you look in the rules manual, you can see the restrictions placed on the width of the obstacles.

[andrewwski]

At NY Lake Erie/Niagara regionals, closest Laser Shoot was 3 mm away. There were also ones at 11 mm, 14 mm, 30 mm, 55 mm, and 80 mm. The rest were >200 mm.

I'll post a copy of the test next week, as there were a significant amount of questions on the test that were pulled from a pool used elsewhere in the state, and some regionals aren't until next week.