What is Reflection: Definition and 953 Discussions
Reflection is the change in direction of a wavefront at an interface between two different media so that the wavefront returns into the medium from which it originated. Common examples include the reflection of light, sound and water waves. The law of reflection says that for specular reflection the angle at which the wave is incident on the surface equals the angle at which it is reflected. Mirrors exhibit specular reflection.
In acoustics, reflection causes echoes and is used in sonar. In geology, it is important in the study of seismic waves. Reflection is observed with surface waves in bodies of water. Reflection is observed with many types of electromagnetic wave, besides visible light. Reflection of VHF and higher frequencies is important for radio transmission and for radar. Even hard X-rays and gamma rays can be reflected at shallow angles with special "grazing" mirrors.
With the passing of Pope John Paul ll, perhaps some reflection on religious beliefs is appropriate. Religion is defined as a set of beliefs concerned with explaining the origins and purposes of the universe, usually involving belief in a supernatural creator and offering guidance in ethics and...
Hello! I'm having difficulty solving this problem, I was wondering if you can help me solve it.
Light is incident in air at an angle on the upper surface of a transparent plate, the surfaces of the plate being plane and parallel to each other.
A ray of light is incident at an angle of 66.0...
Reflected light will experience a 180 degree phase change when it reflects from a medium of higher index of refraction and no phase change when it reflects from a medium of smaller index. This is very well known. However i am wondering why that is ? Can anyone give me some calculations that...
Radio waves of wavelength 250 meters from a star reach a radio telescope by two separate paths. One is a direct path to the receiver which is situated on the edge of a cliff by the ocean. The second is by reflection off the water. The first minimum of destructive interference occurs when the...
A corner reflector is to be made from a triangular prism with index of refraction n=2.56, as shown in the diagram on your assignment. What is the maximum angle (in °), with respect to the normal to the front surface of the prism, (theta), such that total reflection will occur?
Ok this must be...
I understand that a laser beam shining onto a diffraction grating produces a 0th order, 1st order etc... diffracted beam. My question is: What is the wavelength of the specular reflection [0th order beam] off the grating in regards to the wavelength of the incident beam?
Prove mathematically that when a plane mirror is rotated an angle theta about an axis through its center, the angle of deflection of a light is equal to 2theta. How am i to show draw this out? I have already drawn my points and lined up my angles with and without the mirror rotated. I don't know...
I am currently doing a PhD on the subject of solar sailing (if you don't know what that is and are curious enough, a quick google search on "Solar sailing" will give you a plethora of websites that will explain it for you). Solar sails depend crucially on forces generated when a photon is...
If monochromatic light of the same amplitude is shown on a closed hollow black box and a closed black box filled with iron, will there be a difference in the intensity of light that is reflected back due to differences in the absorption of light in the two boxes?
I am going to start out with a simple thought experiment:
A particle is moving towards a wall at a 90 degree angle. The wall is perfectly smooth; therefore, when the particle bounces off, it will be traveling along the same path as it did when it came in.
Does the ball ever come to a...
hello
:rolleyes: i have these questions that i don't know how or what to do :rolleyes:
:confused: Matt drops a water balloon from a balcony 15m up. As it falls, someone calls out 2.0 s after release to warn the bystanders below. If the air temperature is 20 C and the people can move...
Reflection in Mirrors! AAARRRGHHHH
>> How many times will the incident beam be reflected by each of two parallel mirrors that are 1.60m high and 1.40m apart? The beam is aimed at the left mirror at 5 degrees from the horizontal.
Okay I am completely lost here. I've read over all my...
I am struggling with the following problem. I believe it shouldn't be hard - i must be missing something :confused: ?
A tuning fork generates sound waves with a frequency of 246 Hz. The waves travel in opposite directions along a hallway, are reflected by end walls, and return. The...
This is a 'How did I do this?' teaser.
A couple of notes first:
- The picture I include is simulated (Googled for a generic shot). Sorry, best I could do without the original. Ignore the fact that a] it's not me, and b] that the pic is indoors.
- Even though this is a simulation, I actually...
What if you are in a room and the walls, floor and ceiling are all perfect reflectors, and there's a light on in the middle of the room. How bright will it get in there?
I once had a co-worker and close friend, who was a 2nd degree black belt in Sho en ru (sp?) Karate and had his own dojo. He was practicing, teaching and of course learning a form of Zen meditation. He told that the way he looked at it was that we were all travelers on the same river. Some of us...
AP PHYSICS PROBLEM...i forgot the formula, someone help me solve! This won't take lon
Light of frequency 6.0 x 1014 hz strikes a glass/air boundary at an angle of incidence, ø1. The ray is partially reflected and partially refracted at the boundary as shown. The indices are shown.
(a)...
Faster than c!
hi
I read that the refractive index(n) for X-rays in meterials are less than 1(very little less than 1). I got confused ..I am using X-ray reflection at the moment. But I am not convinced by the fact that n<1 means faster than c(velocity of light in vacuum or in air)!
hope...
Need some help on a practice physics problem.
You need to place a mirror on the left wall, so that the reflected light from the bulb exactly fills the right wall.
ceiling
_________________________
| |
|...
Hello!
I am having a problem with this problem about the reflection of a "radio wave" in the high atmosphere. (ionosphere)
"A short-length wave receiver receive two signals from a distant source at 500Km, beeing those signals, one from the normal conduction through the atmosphere and the...
imagine that i have a pair of LEDs throwing light on the same point on a piece of paper. This is possible if the LEDs are inclined equally at an angle to the normal coming out of paper, right?
now if i consider two rays hitting the paper at the same point, then where can i explain the...
imagine that i have a pair of LEDs throwing light on the same point on a piece of paper. This is possible if the LEDs are inclined equally at an angle to the normal coming out of paper, right?
now if i consider two rays hitting the paper at the same point, then where can i explain the...
Hi,
I'm new here...
I already read about how the signals are transmited through the fibre optical cables... total internal reflection
But what I don't understand is the another day I was scribbling it on a piece of paper (the total internal reflection that is)... I noticed that from the way...
The packet doesn't explain this concept very well, and the book doesn't seem to explain it at all.
A glass surface (n = 1.5) is coated with a film with an index of refraction n=1.3. If light of frequency 6x10^14 cps is incident almost normally on the film, find the minimum thickness that...
Hi,
Right now I am solving some exercises in connection with wave optics. If we have three layers of different materials (ex. air, gasoline, water) and we send a light ray through these layers and we calculate the wave length of the reflected rays, then we use these formulas:
D = N*l; (D =...
The Question:
A 45-45-90 prism is immersed in water. What is the minimum index or fefraction the prism must have if it is to reflect totaly a ray incident normally on one of its faces.
Now, we have found this question a bit hard to understand.
We assume that light is hitting one of the...
i have a somewhat elusive question (for me) about light. when you drop a bouncy ball, after it hits the ground, right before it bounces back up, its velocity is zero. correct? it becomes troubling when the ball is replaced with light. when light is reflected straight back to its source, it...
I have a homework problem that I'm not sure how to figure out. What equation should I use for this?
A person whose eyes are 1.8 m above the floor stands in front of a plane mirror. The top of her head is 0.12 m above her eyes. What is the height of the shortest mirror in which she can see...
Need urgent help with light reflection problems
Here are my problems:
1) A beam of light has a wavelength of 610 nm in vacuum.
a: What is the speed of this light in a liquid whose index of refraction at this wavelength is 1.45?
I used n=c/v to get 2.07x10^8 m/s. This is correct.
b: What is...
If a beam of light shines from the 10 on the face of a clock, reflects off a mirror in the center and strikes the 5, what is the angle of reflection.
If anyone could help me, it would be much appreciated tyty.
ok, i need help with this one question. the diagram that goes with this question is at the following website: http://courseweb.edteched.uottawa.ca/phy1102A/Assignments/Problems/PHY1102A-Assignment%204_files/image005.jpg
i tried attaching it but it was too big. ok so here it is:
A ray of...
Hello,
I am trying to write the transfer matrix for surface with an s-polarized em wave incident on it. I want to look at the case of total internal reflection- but I don't know if it makes any sense to look at the transfer matrix in that case, since there is no transfer across the boundary...
this is by no means polished. i will be working out my thoughts as i write.
whenever i try to understand the concept of self, i visualize a tree. i am the tree but this physical me might only be a branch of the total me. the trunk is my core being(soul, spirit, etc?) and the big branches...
I'm doing an response on a little experiment done in class. I'm having trouble understanding some parts. If someone could reply to the information below, it would really be appreciated.
A large beaker is filled with water, it is covered on the outside by construction paper (any coulour you...
black surfaces apparently absorbs all light, that's why it appears black, but does it ever reflect light off its surface?
what if its a polished black suface..we could actually see our own reflection on these surfaces.. so is there light being reflected at all? is there any difference from the...
If anyone could provide some insight into how I might go about solving this problem it would be greatly appreciated.
Q: A ray enters the flat end of a long rectanglular block of glass that has refractive index n_2 as shown in the following figure. Show that all the entering rays can be...
In basic science class, when talking about light and the colors of objects, people will say that the pigments absorb some light, but the light that represents the color you see is reflected.
Is light actually reflected (the same photons/waves still exist and are now traveling in a different...
The drawing shows an optical fiber that consists of a core made of flint glass (nflint = 1.667) surrounded by a cladding made of crown glass (ncrown = 1.523). A beam of light enters the fiber from air at an angle q 1 with respect to the normal. What is q 1 if the light strikes the core-cladding...
One thing that has allways disturbed my mind is the correct understanding of lightinteractions in nature.
When we're talking about light reflection (light that is reflected in an arbitrary direction, not like mirrors) is it really reflections or is it new light created by the incoming light...
When light is incident on a surface of water, for example, some of the light is reflected and some is transmitted and refracted. As I recall, the percentage of light that gets reflected will be determined by the quantum probability that light will reflect at that interface.
First...
Hi all. I just have a few questions regarding light refraction and reflection.
At sunset, the sun seems to be higher in the sky than it really is- correct? What causes this?
Which color of light is refracted least by a glass prism? How do each of the colors separate through a prism to...
I have a simple question to which, I assume, the answer will be quite complicated. I asked my physics teacher this question and all he would say was, "It is known."
So without beating me to death with physics can anyone tell me why waves diffract? For instance, electron diffraction around a...
Hope this is the right forum. Rather daunting task to pick the right forum when you don't understand what differentiates each topic...
Anyhow, I've been reading Feynman "QED The Strange Theory of Light and Matter" (lectures). Actually, I've read it about 3 times, cover to cover. I get some of...
A convex mirror and a plane mirror are placed facing each other and 28cm apart. Midway between them and on the principal axis of the convex mirror a small luminous object is placed. If the distance between the two images observed on looking into the plane mirror is 24 cm, calculate the radius of...