What is the thickness of the paper in this interference experiment?

AI Thread Summary
The problem involves calculating the thickness of a piece of paper placed at the end of a 4 cm long air wedge, where interference fringes are observed with light of wavelength 639 nm. A dark fringe is noted at both the wedge's vertex and the paper end, with 56 bright fringes in between. The formula used for the calculation is delta X = L (lambda / 2t), where t represents the thickness of the paper. After working through the calculations, the individual expresses relief at solving the problem, indicating a successful resolution. The discussion highlights the application of interference patterns in determining material thickness.
Matt1234
Messages
141
Reaction score
0

Homework Statement



A piece of paper is placed at the end of an air wedge 4 cm long. Interference fringes appear when the light of wavelength 639 nm is reflected from the wedge. A dark fringe occurs at both the vertex of the wedge and at its paper end, and 56 bright fringes appear between. Calculate the thickness of the paper.

Homework Equations




delta X = L (lambda / 2t)

where t is the thickness of the paper
lambda = wavelength
l = length of air wedge
X = distance between fringes.
 
Physics news on Phys.org
nevermind i got it I am stupid :(
 
Thread 'Variable mass system : water sprayed into a moving container'

Thread 'Variable mass system : water sprayed into a moving container'

Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
View full post »

Similar threads

Thin film interference—find the height of a wedge
Replies
3
Views
2K
Second bright fringe in Young's Experiment
Replies
3
Views
1K
A problem involving thin film interference
Replies
2
Views
2K
Interference in Thin Films: Determining SiO2 Layer Thickness Using a Wedge Setup
Replies
11
Views
2K
What kind of fringe is seen at the left edges of the slides?
Replies
10
Views
2K
Double Slit Wave Interference - what is m?
Replies
1
Views
2K
Interference pattern for thin films
Replies
3
Views
2K
Question on thin film interference
Replies
1
Views
3K
Diffraction & Interference - interference fringes per cm
Replies
3
Views
3K
Hair/wire laser diffraction interference pattern
Replies
5
Views
4K

Hot Threads

Recent Insights

Back
Top