At what angle does the light leave the glass

AI Thread Summary
The discussion focuses on solving a physics problem involving light refraction through a glass block surrounded by a liquid. The key equation used is Snell's law, which relates the angles of incidence and refraction based on the refractive indices of the materials involved. The initial attempt at a solution included an incorrect value of 1.6, leading to confusion about its origin. Participants emphasize the need to apply Snell's law twice—once at the interface between the liquid and glass, and again at the glass and air interface. Proper calculations and understanding of the angles are crucial for arriving at the correct answer.
phys62
Messages
53
Reaction score
0

Homework Statement


The drawing shows a rectangular block of glass (n = 1.52) surrounded by a liquid with n = 1.79. A ray of light is incident on the glass at point A with a 30.0° angle of incidence. At what angle does the ray leave the glass at point B?

http://edugen.wiley.com/edugen/courses/crs1507/art/qb/qu/c26/ch26p_18.gif


Homework Equations


n1*sin(theta1)=n2*sin(theta2)


The Attempt at a Solution


I solved this and got the right answer by doing the steps below, however I have no idea why I put 1 in the denominater, and this is not the correct way to solve it because my friend's problem is not working out. Please help me figure out the proper way to solve this, as I've tried everything I can think of!

sin(theta2) = (1.6 sin30)/1 = 53.13 degrees
 
Physics news on Phys.org
Hi phys62! :wink:
phys62 said:
sin(theta2) = (1.6 sin30)/1 = 53.13 degrees

Where did 1.6 come from? :confused:

Show us your full calculations, and then we'll know how to help. :smile:
 
You need to apply Snell's law twice: Once at A; once at B. And you need to relate the angle of refraction at A to the angle of incidence at B.
 

Thread 'Errors and significant figures'

I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
View full post »
Thread 'Collision of a bullet on a rod-string system: query'

Thread 'Collision of a bullet on a rod-string system: query'

In this question, I have a question. I am NOT trying to solve it, but it is just a conceptual question. Consider the point on the rod, which connects the string and the rod. My question: just before and after the collision, is ANGULAR momentum CONSERVED about this point? Lets call the point which connects the string and rod as P. Why am I asking this? : it is clear from the scenario that the point of concern, which connects the string and the rod, moves in a circular path due to the string...
View full post »
Thread 'A cylinder connected to a hanging mass'

Thread 'A cylinder connected to a hanging mass'

Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
View full post »

Similar threads

At what angle does the light leave the glass?
Replies
3
Views
11K
Optics: refraction and reflection
Replies
1
Views
2K
Angular spread of light rays passing through a prism
Replies
6
Views
5K
Violet light refraction from air to glass
Replies
1
Views
2K
Angle of Refraction Given Wavelength & Speed of Light in Air & Glass
Replies
3
Views
2K
Investigate one factor that affects the angle of refraction
Replies
1
Views
3K
Refraction of Light question assistance needed
Replies
3
Views
2K
Multiplayer Refraction, Incident Angle
Replies
3
Views
11K
What Is the Angle of Refraction for a Light Ray Incident on Glass at 30 Degrees?
Replies
2
Views
2K
Find the Angle of Incidence for Total Internal Reflection in a Glass Sphere
Replies
4
Views
2K

Hot Threads

Recent Insights

Back
Top