Calculating the Fringe Width without the value of its Wavelength

Click For Summary
SUMMARY

The discussion focuses on calculating the fringe width (Y) in a Young's double-slit experiment using given measurements of fringe spacings and distances. The slits are spaced 0.60mm apart, and the distance across 20 fringe spacings changes from 58mm to 74mm when the screen is moved 0.80m away. The relationship Y1/Y2 = D1/D2 is established to find the initial distance (D1) from the slits to the screen, which is essential for determining the wavelength (λ) of the laser light used in the experiment.

PREREQUISITES
  • Understanding of Young's double-slit experiment principles
  • Familiarity with fringe width calculations
  • Knowledge of the relationship between distance, wavelength, and slit spacing
  • Basic algebra for solving equations
NEXT STEPS
  • Research the derivation of the fringe width formula Y = D(λ) / d
  • Learn about the effects of varying slit separation on fringe patterns
  • Explore methods for measuring wavelength using interference patterns
  • Study the impact of distance changes on fringe visibility and spacing
USEFUL FOR

Students studying optics, physics educators, and anyone interested in experimental physics and wave interference patterns.

AJ786
Messages
3
Reaction score
0

Homework Statement



Young's fringes, produced by monochromatic laser light passing through slits 0.60mm apart, are viewed on a screen. The distance accrose 20 fringe spacings on the screen is 58mm. When the screen is moved 0.80m away from the slits, the distance across 20 fringe spacings becomes 74mm.

Homework Equations



Y = D(lamda) / d

Y = Fringe Width
D = Distance from slits to screen
d = spacing between slits
(lamda) = Wavelength

The Attempt at a Solution

 
Last edited:
Physics news on Phys.org
In the experiment wavelength and slit width is constant. There fore
Y1/Y2 = D1/D2.
Y1 and Y2 is given. D1 is not given. But D2 = D1 + 0.80 m.
Substitute these values in the above relation and find D1.
Then using the relevant equation, you can find the wavelength.
 
Are Y1 and Y2 0.60mm and 74mm as Y is what I need to calculate so surely this would not be given to me within the question ?
 
Last edited:

Similar threads

  • · Replies 3 ·
Replies
3
Views
2K
Replies
6
Views
3K
  • · Replies 3 ·
Replies
3
Views
1K
  • · Replies 1 ·
Replies
1
Views
2K
Replies
4
Views
2K
  • · Replies 1 ·
Replies
1
Views
1K
Replies
7
Views
5K
  • · Replies 5 ·
Replies
5
Views
3K
  • · Replies 6 ·
Replies
6
Views
1K
  • · Replies 5 ·
Replies
5
Views
4K