Partial Reflection-Partial Refraction

Click For Summary
Partial reflection and partial refraction can occur with all types of waves, not just light, as evidenced by phenomena such as total internal reflection. The discussion highlights that this behavior is not exclusive to light, with examples provided from water waves and spring waves demonstrating similar principles. The concept of critical angles and wave behavior at boundaries is applicable across various wave types. Additionally, the conversation touches on the differences between light and water waves, noting that light exhibits particle-like properties while water does not. Overall, the principles of wave behavior are universal and can be explored through practical experiments like using a ripple tank.
whoareyou
Messages
162
Reaction score
2

Homework Statement



Can partial reflection-partial refraction occur with all waves (ie. other than light)?

Homework Equations





The Attempt at a Solution



My textbook constantly refers to light and apparently so does Google.

"For still larger incident angles there is no refraction at all,with all the wave energy being reflected; this behaviour of light is referred to as total internal reflection. This phenomenon is analogous to the total internal reflection of light."

First it says that the behavior of light is referred to as total internal reflection and then it says it is analogous to the total internal reflection of light, so it seems that it can apply to all kinds of waves. Also, this chapter of my textbook is not specifically for light, its just a general introduction to waves in two dimensions.
 
Physics news on Phys.org
Try it out with water waves :)
(To get two "refractive indexes", change the depth of the water sharply at the "boundary".)

[edit] I did a reality check on how easy it would be to google for this, and it took several attempts, so I decided to just show it to you...
See below:
http://www.thephysicslaboratory.org/Essays_Unit_2/Wave_Tank_2.1_files/Refraction.jpg
... here water waves are moving from shallow to deep water - you can clearly see the refraction,
but if you look carefully you can also see the faint reflected waves as they interfere with the incoming ones, giving it a cross-hatched look.

[Everything looks wobbly because of the refraction of light in the water - the photographer would have done better with a darker room and a strobe-light mounted close to the water - a darker lower surface to the tank would help too.]
http://www.thephysicslaboratory.org/Essays_Unit_2/Wave_Tank_2.1.html

You can also see it in waves on a spring - though it's clearer with pulses - this time use a heavy and a light slinky and send a pulse from the light to the heavy end - you get an inverted reflected pulse, and a small transmitted pulse.
 
Last edited by a moderator:
Ok Thank You!

Also, does total internal reflection only apply to light?
 
All the wave phenomena apply to anything with wave-like properties. Which would be everything (with the possible exception of cats - ask Schodinger...)

You can also do lenses, prisms etc.
There are differences, water does not have particle-like properties while light can.
You can also get waves of probability which gets really interesting.

Have a play with a ripple-tank like in the pic ... or just draw the rays on the pic and you'll be able to work out the critical angle for total internal reflection. (I think the frequency of the waves and the scale is in the source page.) It's just geometry... you know how total internal reflection works right?

Hmmm ... unable to find pics of this.
In general, there seems to be a lack of this sort of photo online... looks like I may have a summer project.
 
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?

Similar threads

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