Homework Help: Young's double slit experiment question.

1. Jul 2, 2007

Mr Virtual

Hi
I don't know whether this is a homework-type question or not, so I am posting it here.

In young's double slit experiment the interference pattern is found to have an intensity ratio between bright and dark fringes as 9. What does this imply:
(Below are the options provided in the book. One of them is the correct answer)
1. the intensities at the screen duo to the two slits are 5 nd 4 units respectively
2. the intensities at the screen are 4 units and 1 unit respectively
3. the amplitude ratio is three
4. The amplitude ratio is two

As far as I think, option 3 is correct, because if amplitude ratio is 3, then probability ratio will automatically be (amp^2)=3^2=9.
Am I right?

Mr V

2. Jul 2, 2007

G01

The intensity is proportional to the amplitude squared so I would agree with you. I would also pick #3.

Last edited: Jul 3, 2007
3. Jul 2, 2007

nrqed

I know this is just a typo but just to make sure that it does not cause confusion for the OP, G01 meant to say that the intensity is proportional to the amplitude squared.

sorry, it's just a tiny detail and I know that G01 knows that.

Cheers

4. Jul 3, 2007

Mr Virtual

Thanks a lot.

Mr V

5. Jul 3, 2007

G01

Thanks for pointing it out. I have fixed the typo in my above post.