Calculating the Fringe Width without the value of its Wavelength

Click For Summary
To calculate the fringe width without the wavelength, the relationship Y1/Y2 = D1/D2 can be utilized, where Y1 and Y2 are the fringe widths for two different distances from the slits. Given that the distance across 20 fringe spacings changes from 58mm to 74mm when the screen is moved 0.80m away, D2 can be expressed as D1 + 0.80m. By substituting the known values into the equation, D1 can be determined. Once D1 is found, the wavelength can be calculated using the fringe width equation. This approach allows for the calculation of fringe width without directly knowing the wavelength.
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:

Thread 'Magnitude of buoyant force in fluids of different densities'

The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?
View full post »

Similar threads

Second bright fringe in Young's Experiment
  • · Replies 3 ·
Replies
3
Views
1K
Number of bright fringes given by diffraction grating on a screen
  • · Replies 6 ·
Replies
6
Views
3K
Diffraction pattern from a grating
  • · Replies 3 ·
Replies
3
Views
967
How do you calculate finge width without the wavelength ?
  • · Replies 1 ·
Replies
1
Views
2K
Interference: Factors that reduce the widths of primary maxima
  • · Replies 4 ·
Replies
4
Views
2K
With the info given, what are 3 ways to calculate wavelength?
  • · Replies 1 ·
Replies
1
Views
1K
What is the Number of Fringes in a YDSE with Given Parameters?
  • · Replies 7 ·
Replies
7
Views
5K
Interference Fringes in a Diffraction envelope
  • · Replies 5 ·
Replies
5
Views
3K
Predicting a decrease in fringe distance (equations)
  • · Replies 6 ·
Replies
6
Views
1K
Inteference Fringes of Double Slit Experiment in Water
  • · Replies 3 ·
Replies
3
Views
3K