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1answer
880 views

What is limiting line in series spectrum?

The wavelength of first line in the Balmer Series is 'whatever(in nm)' . Calculate the wavelength of the second line and the 'limiting line' in the Balmer Series. I found this question in an ...
0
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2answers
328 views

Change in Wavelength of a Photon Relation to Energy (specifically Compton Effect)

Given a photon dropping from $\lambda_1$ to $\lambda_2$, its energy will drop from $\frac{hc}{(\lambda_1)}$ to $\frac{hc}{(\lambda_2)}$. However, I was wondering if there is any significance in the ...
4
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2answers
117 views

Diffraction pattern when wavelength tends to zero

While studying about Fresnel and Fraunhofer diffraction, I came across a statement which says that the fringes disappears and the image would take on the limiting shape of the aperture when wavelength ...
0
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0answers
94 views

Radar as range detector between cars-static sender vs dynamic sender

Say I have a radar transmitter on a car,used to detect its distance from a car in front of it by measuring the doppler shift on the reflected wave. i.e Car 1 is the source, its wave gets reflected by ...
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2answers
222 views

How is wavelength actually related to space (/distance)?

Is a photon of 400nm in wavelength "smaller" than a photon of 1km in wavelegth?
0
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1answer
64 views

Relationship between tones made by a piano

If a piano were to be tuned perfectly with the equal temperament system, what would be the relationship between standing waves from one note to the next? How would the frequency and wavelength of ...
0
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1answer
152 views

What is the wave length of the entire universe?

In quantum physics, particles are also waves. Larger particles have shorter wave lengths, and macroscopic objects have extremely short wave lengths so that the wave aspect can be ignored, and ...
5
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4answers
2k views

Radio antennas that are much shorter than the wavelength

From my limited experience with ham radio when I was a kid, I expect transmitting and receiving antennas to have lengths that are on the same order of magnitude as the wavelength, and in fact I recall ...
5
votes
2answers
800 views

Is the de Broglie wavelength of a photon equal to the EM wavelength of the radiation?

Is the de Broglie (matter) wavelength $\lambda=\frac{h}{p}$ of a photon equal to the electromagnetic wavelength of the radiation? I guess yes, but how come that photons have both a matter wave and an ...
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0answers
51 views

How does QED deal with wavelength of quanta [duplicate]

Since QED treats photons as individual units (quanta) how does it treat the concept of the "wavelength" associated with the photon?
8
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2answers
3k views

De Broglie wavelength, frequency and velocity - interpretation

Two fundamental equations regarding wave-particle duality are: $$ \lambda = \frac{h}{p}, \\ \nu = E/h .$$ We talk about de Broglie wavelength, is it meaningful to talk about de Broglie frequency ...
1
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1answer
681 views

Finding the wavelength of an electron in its ground state?

To find the wavelength of an electron in its ground state in a hydrogen atom, would I or could I do the following? Use the ground state energy (-13.6eV) in $E^2 = m^2c^4 + p^2c^2$ Solve for $p$ Use ...
2
votes
1answer
257 views

Understanding de Broglie Wavelengths

I understand the derivation and calculation of de Broglie wavelengths, but what exactly does the wave of a particle represent? What does the wavelength of a particle mean? I'm assuming it's not the ...
3
votes
2answers
910 views

How does the wavelength change in relativistic limit?

In the text, it reads that the momentum of a particle will change if it is moving at speed close to light speed. In the general case, the wavelength is given as $$ \lambda = \frac{h}{p} $$ and $$p ...
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0answers
152 views

Are EM waves scattered the most when the wavelength and the obstacle have a similar size?

I heard that when the wavelength and obstacle are similar in size, the scattering is the greatest. Is this true?
2
votes
2answers
1k views

Why does Planck's law for black body radiation have that bell-like shape?

I'm trying to understand Planck's law for the black body radiation, and it states that a black body at a certain temperature will have a maximum intensity for the emission at a certain wavelength, and ...
2
votes
0answers
484 views

How does a Fresnel rhomb work (half and quarter wave plate)?

How does a Fresnel rhomb work (half and quarter wave plate)? I am aware of birefringence, which creates a phase shift of $\Delta\phi=\dfrac{2\pi\Delta nL}{\lambda_0}$. But this doesn't explain how a ...
2
votes
1answer
128 views

Holograms? Sci Fi or future fact?

Based on how light behaves when it passes through mediums, i.e. the wavelength of light changes when it passes through mediums of different refractive indexes, wouldn't it be possible to convert ...
5
votes
2answers
616 views

If photons move linearly, what's actually stopping them from passing through a microwave oven mesh?

So, my understanding is that the wavelength of a photon is the distance traveled in the time it takes it's magnetic field to oscillate. And it's inversely proportional to it's energy and it's ...
1
vote
1answer
805 views

De broglie equation

What is the de Broglie wavelength? Also, does the $\lambda$ sign in the de Broglie equation stand for the normal wavelength or the de Broglie wavelength? If $\lambda$ is the normal wavelength of a ...
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2answers
11k views

Relationship between frequency and wavelength [closed]

I am currently writing up a report for science class on the relationship between frequency and wavelength. And so I was wondering if anyone knew where I could find published results (literature value) ...
3
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3answers
1k views

Why aren't the graphs for black body radiation straight lines?

We know that a wave which has greater frequency will have low wavelength and high energy. So, by decreasing the wavelength, the frequency and consequently energy (intensity) of that wave will increase ...
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3answers
1k views

Does light change color on its way through a window? [duplicate]

Looking at the refractive index of glass, it's around $1.6$. Then the speed of light $x$ through light should be given by $$ 1.6 = \frac{3.0\times10^8}{x}, $$ so $x$ is about ...
-1
votes
1answer
186 views

Are the speeds of the different wavelengths of visible light different or varying in a medium such as air?

Are the speeds of the different wavelengths of visible light different or varying in a medium such as air? If so, please inform by how much? Also, even if the wavelength speeds vary minimally, please ...
0
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2answers
285 views

Wavelength comparison of two waves

Is there any non-digital (naturally existing) mechanism to compare two or more waves in such a way: ...
2
votes
1answer
1k views

Laser Coherence Length/Time

Scenario: Imagine a collimated beam of white light falling on one refracting face of a prism. Let the light emerging from the second face be focused by a lens onto a screen. Suppose there is linear ...
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2answers
5k views

Frequency of the sound when blowing in a bottle

I'm sure you have tried sometime to make a sound by blowing in an empty bottle. Of course, the tone/frequency of the sound modifies if the bottle changes its shape, volume, etc. I am interested in ...
-2
votes
1answer
373 views

How to reconstruct information from a graph of an oscillation? [closed]

We are given a graph of the position of a wave (amplitude). How can we calculate the wavelength, frequency and the maximum speed of a particle attached to that wave? We have Speed = wave length ...
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2answers
12k views

Why is Near Field Communication (NFC) range limited to about 20cm?

Near Field Communication (NFC) operates at 13.56 MHz. Near Field is the region situated at a distance r << λ λ = c/f ...
1
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0answers
115 views

How do you super impose two or more signals to occupy a fix area of space with the resultant summed wave?

Is it possible to super-impose two or more signals all sent from different directions as a standing wave with the resulting summed wave occupying a fix area of space that is also a complex area? Do ...
3
votes
3answers
313 views

What if $\gamma$-rays in Electron microscope?

I was referring Electron microscopes and read that the electrons have wavelength way less than that of visible light. But, the question I can't find an answer was that, If gamma radiation has the ...
3
votes
1answer
425 views

Bragg condition for transmission: Why is the full diffracted angle Two times Theta? Or isn't it?

On a Bragg reflection with incomming angle Theta the total diffraction angle of the incomming wave is 2*Theta, of course. But I have Bragg transmission with electrons on a graphite crystal ...
0
votes
2answers
1k views

Is carbon dioxide a greenhouse gas? [duplicate]

Possible Duplicate: What experiments prove the greenhouse effect? I am seeking for a proof that CO2 is a greenhouse gas. I posted this on Skeptic.SE recently but found no help in seeking ...
8
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3answers
469 views

Why do rainbows have distinct colors?

When I searched on the Internet for the reason of formation of rainbows, I got many explanations like this one & this. All the explanations consider only one spherical water droplet (like this ...
1
vote
1answer
144 views

What's the wavelength of an electron after hitting a potential barrier?

I have this question: An electron with Energy $E = 40 eV$ hits a potential barrier with $E_0 = 30 eV$. What is the wavelength of the electron after hitting the potential barrier? I worked from ...
0
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2answers
3k views

Can the equation $v=\lambda f$ be made true even for non sinusoidal waves?

The known relation between the speed of a propagating wave, the wave length of the wave, and its frequency is $$v=\lambda f$$ which is always true for any periodic sinusoidal waves. Now consider: ...
1
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0answers
49 views

What is the Zero-dispersion wavelength?

There are a decent number of complex mathematical descriptions of the zero-dispersion wavelength online, but I can't seem to find any basic explanations. So to be redundant, what is it?
4
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10answers
2k views

Why do we think of light as a wave?

I've read that light travels in a straight line and has a wavelength of 400nm to 700nm. But I don't understand why does it have a wavelength and what creates its wavelength? I agree with the concept ...
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3answers
5k views

Is all kind of light same speed?

Is there any speed different between blue or red color? Is there speed different? or there are same speed?
1
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1answer
962 views

Find the dispersion of the slab?

I've been having trouble with this for a few days and already used up all my tries on the homework for it, but have the final is coming next week. Thus I would like to know how do this, however I ...
8
votes
2answers
4k views

In electromagnetic radiation, how do electrons actually “move”?

I've always pictured EM radiation as a wave, in common drawings of radiation you would see it as a wave beam and that had clouded my understanding recently. Illustration on the simplest level: ...
10
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3answers
48k views

Why does wavelength change as light enters a different medium?

When light waves enter a medium of higher refractive index than the previous, why is it that: Its wavelength decreases? The frequency of it has to stay the same?
18
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7answers
13k views

What determines color — wavelength or frequency?

What determines the color of light -- is it the wavelength of the light or the frequency? (i.e. If you put light through a medium other than air, in order to keep its color the same, which one would ...
2
votes
3answers
2k views

Some questions about car radio and cellphone antennas

1-Why the antenna of the radio of cars is located outside the car and not inside? 2-If the answer to 1 is because that cars are like Faraday cages then how come my cell phone can receive signal ...
2
votes
2answers
1k views

Matter waves and de Broglie wave length

The wavelength of a particle of momentum p is calculated using De Broglie relation. The de Broglie relation was postulated for what is called a matter waves. Now according to the statistical ...
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3answers
3k views

Why is it necessary for an object to have a bigger size than the wavelength of light in order for us to see it?

I keep hearing this rule that an object must have a bigger size than the wavelength of light in order for us to see it, and though I don't have any professional relationship with physics, I want to ...
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votes
2answers
143 views

Energy required to reach 1 wavelength [closed]

I was curious if there was a forumla to find the energy required to reach 1 wavelength in a given substance. (or a vacumn if that's too hard). I am also wondering if this number can tell us anything ...
1
vote
1answer
147 views

Will a photon emitted from something moving quickly have a shorter wavelength?

If a photon is emitted from a light source moving at any speed, the photon will nonetheless always move at c (assuming it is emitted in a vacuum.) If the speed of a photon's emitter cannot influence ...
1
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1answer
269 views

Does interchangeable wavelength LED exist in NIR?

Does exist a led material that allow to interchange the emitted wavelenght in near IR spectrum? Thanks
5
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1answer
928 views

Visible light spectrum to color space

I need to be able to convert an arbitrary emission spectrum in the visible spectrum range (i.e. for every wavelength between 380 and 780, I have a number between 0 and 1 that represents the ...