# Physics

Hi! I need help with this question...
A double slit experiment, using light of wavelength 600 nm, results in fringes being produced on a screen. The fringe separation is found to be 1.0 mm.

When the distance between the double slits and the viewing screen is increased by 2.0 m, the fringe separation increases to 3.0 mm. What is the separation of the double slits producing the fringes?
--
Supposedly the answer is 0.6 mm, but I've been getting 1.2 mm. Where did I go wrong?

x=(wavelength*distance)/fringe separation

Eq 1 => 1*10^-3 = 6*10^-9 (D) /A
Eq 2 => 3*10^-3 = 6*10^-9 (D+2)/A

Help is much appreciated!!! :D

1. 👍 0
2. 👎 0
3. 👁 226
1. Oh my gosh! I forgot nano is 10^-7. Oops! :C

1. 👍 0
2. 👎 0
posted by Leiah_
2. 600 nm= 600E-9=.6E-9 meters=6E-7meters

1. 👍 0
2. 👎 0
3. nano is -9....

1. 👍 0
2. 👎 0
4. Hello Bob! Thanks for aswering :)
Oh my gosh, nano is ^-9, what am I saying haha, so confused :C

I think I've been using 6E-9 but I just can't seem to get it...

1. 👍 0
2. 👎 0
posted by Leiah_
5. using light of wavelength 600 nm, " IS NOT 6E-9, it is 600 E-9, or 6E-7

1. 👍 0
2. 👎 0
6. OH! Ok, I redid my working using 6E-7 this time :)

Somehow, I managed to get a 6 in my answer haha, but not 0.6 mm.

Eq 1 -> 3*10^-3 =6*10^-7(D+2)
Eq 2 -> 1*10^-3 =6*10^-7(D)

A=6*10^-4D
A=2*10^-4(D+2)

6*10^-4D=2*10^-4(D+2)
D=1.99997
A=2*10^-4(-1.9997+2)
=6*10^-9 m
=6*10^-6 mm

Sorry for the messy working :C
Still can't get it!!

1. 👍 0
2. 👎 0
posted by Leiah_
7. UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS
General Certificate of Education
PHYSICS
9702/12
Paper 1 Multiple Choice
October/November 2010
1 hour
Soft clean eraser
Soft pencil (type B or HB is recommended)

1. 👍 0
2. 👎 0
8. I took a look at the paper but they only give the answer and they don't show the working method :C

1. 👍 0
2. 👎 0
posted by Leiah_

## Similar Questions

1. ### physices

mean: a double-slit interference experiment is set up in a laboratory using a source of blue monochromatic light of wavelength 475 nm.the separation of two slit is 0.40mm and the distance from the slit to the screen where the

asked by Anonymous on February 20, 2013
2. ### Physics

A double-slit experiment uses coherent light of wavelength 633 nm with a slit separation of 0.100 mm and a screen placed 2.0 m away.

asked by as on December 17, 2016

A double-slit experiment is performed with light from a Helium Neon Laser on two slits 80 micrometers apart. The first bright interference fringe left of the center is spaced 2m from the bright center. How far away from the double

asked by kailey on March 3, 2017
4. ### AP PHYSICS

In a Young's double-slit experiment, the angle that locates the second-order bright fringe is 3.0°. The slit separation is 4.8 10-5 m. What is the wavelength of the light?

asked by Alan on February 16, 2011
5. ### Physics

A double-slit experiment using violet light of wavelength 400 nm produces a spacing of (triangle x). what is expected spacing if red light of wavelength 600 nm used? a) 2/3 (triangle x) b) (triangle x) c) 1.5 (triangle x) d) 3

asked by Jessey on January 7, 2018
1. ### physics

In a double-slit experiment, it is found that blue light of wavelength 460 nm gives a second-order maximum at a certain location on the screen. What wavelength of visible light would have a minimum at the same location?

asked by Anonymous on March 26, 2009
2. ### physics

In a Young's double-slit experiment, the angle that locates the second dark fringe on either side of the central bright fringe is 7.2°. Find the ratio d/λ of the slit separation d to the wavelength λ of the light.

asked by Anonymous on April 17, 2014
3. ### Physics

In the double slit experiment with light, we know that the spacing of the interference fringes (which is what we call the bright spots on the screen) depends on the wavelength of the light. How? Specifically, if you make the

asked by Jacob on August 22, 2012
4. ### physics

Light falls on a double slit with slit separation of 2.45×10^−6m, and the first bright fringe is seen at an angle of 13.8◦ relative to the central maximum. What is the wavelength of the light?

asked by Anonymous on November 11, 2013
5. ### Physics

Using light of wavelength 600.0nm in a double slit apparatus we find delta x = 1.0cm. If we use the same apparatus for light of wavelength 450.0 nm, what is the new delta x on the screen? Delta x = L*lambda/d But L and d are not

asked by Neenah on December 16, 2014

More Similar Questions