Help~total internal reflection

Click For Summary
Total internal reflection (TIR) occurs when light attempts to move from a denser medium to a less dense one, and the angle of incidence exceeds the critical angle determined by the refractive indices. Adding water to the bottom of a beaker changes the refractive index, which affects the critical angle for TIR. This alteration can make submerged objects, like a button, reappear when viewed from above. To understand this phenomenon better, creating a ray diagram for both scenarios—without and with water—can be helpful. Additionally, there are useful YouTube demonstrations that illustrate these concepts effectively.
jadelamlam
Messages
51
Reaction score
0
can anyone explain for me :)?
I have no idea:(
 

Attachments

  • total.jpg
    total.jpg
    39.5 KB · Views: 493
Science news on Phys.org
Which bit are you stuck on?
You know how reflection works? You know Snell's Law?
Or is it you don't know how adding water to the bottom makes the button reappear?
 
Re Simon Bridge :
I know how reflection works and the Snell's Law.Also total internal reflection
But I don't know why adding water to the bottom makes the button reappear
 
TIR depends on the ratio of the refractive indexes ... what happens to the refractive index when you add the water?
 
increases?
 
You can tell more than that. What happens to the ratio of the refractive indexes and what does that mean for the critical angle for TIR?

You need to draw a ray diagram of what is happening in the TIR case, and then repeat for if there is water under the beaker.

There are also youtube demos.
 

Similar threads

Undergrad Outer layer refractive index - total internal refection on waveguide
  • · Replies 2 ·
Replies
2
Views
2K
Is there refraction upon frustrated total internal reflection
  • · Replies 8 ·
Replies
8
Views
4K
What's the amount of energy lost in Total Internal Reflection?
  • · Replies 4 ·
Replies
4
Views
2K
High School Shouldn't the refracted ray be along the boundary here?
  • · Replies 5 ·
Replies
5
Views
2K
High School Reflection from double glazed window
  • · Replies 7 ·
Replies
7
Views
2K
Graduate Iphone Reflection has a pattern
  • · Replies 2 ·
Replies
2
Views
2K
Energy Loss During Total Internal Reflection
  • · Replies 14 ·
Replies
14
Views
4K
How does Total Internal Reflection in a mm/sm fiber work?
  • · Replies 3 ·
Replies
3
Views
2K
Polarisation of Light: Reflection, Critical Angle & Total Internal Reflection
  • · Replies 8 ·
Replies
8
Views
2K
Undergrad How Can I Achieve a Non-Direct Reflection Effect on Plexiglass at 90 Degrees?
  • · Replies 18 ·
Replies
18
Views
2K