Questions tagged [radiation]

Radiation is a process in which energetic particles or energetic waves travel through a medium or space. The particles or waves radiate (i.e., travel outward in all directions) from a source.

Filter by
Sorted by
Tagged with
0
votes
2answers
41 views

Does Unruh radiation potentially explain the Paradox of 'apparent non-radiation of charged particles in a gravitational field'?

The Wikipedia entry on 'Paradox of radiation of charged particles in a gravitational field' does not mention Unruh or Hawking radiation, but I don't see why they wouldn't provide a solution.... ...
1
vote
1answer
46 views

Deflection of Alpha & Beta Radiation in an Electric & Magnetic Field

To explain how alpha and beta particles are deflected, the following two figures have been provided in my textbook but without any explanation for the intensity of the deflections shown: I have two ...
1
vote
1answer
39 views

Interference of em waves

If EM waves interfere, how is it that wave that is in my line of sight does not interfere with wave that is in someone else's line of sight which intersects my line of sight, and consequently make ...
3
votes
0answers
31 views

Cloud chamber shows initial rain effect but no tracks

I am trying to make a cloud chamber but it does not work yet. I do see a rain effect at the beginning which means that the alcohol is condensing and the rain effect slowly disappears as the vapor gets ...
1
vote
0answers
50 views

It seems a stove top coil / burner element defies black body radiation

Most glow charts say that incipient red Heat is 1000 Fahrenheit or 540 Celsius , and bright orange is just shy of 2,000 Fahrenheit or 1093 celsius . But my fluke thermocouple rated at over 2,000 ...
2
votes
1answer
45 views

Confusion over Feynman’s description of the Wu experiment for parity violation

In his lecture on symmetry in physical law, Feynman said: Using a very strong magnet at a very low temperature, it turns out that a certain isotope of cobalt, which disintegrates by emitting an ...
0
votes
0answers
9 views

3D Modelling of Diffuse Reflection

I am currently working on a project dedicated to modelling of solar radiation effect on satellite orbit. Whilst working on it, I come across 2 sorts of reflections involved: specular and diffuse ...
0
votes
2answers
82 views

Detection of day or night?

I was wondering, are there "particles" that can be detected, when one's side of earth is shined on by the sun? I understand that there are cosmic radiations present, which probably will ...
1
vote
0answers
29 views

Spark counter has no spark when fire is put nearby

With a positively charged gold leaf electroscope, $\alpha$ radiation: gold leaves fall rapidly Fire: gold leaves fall rapidly $\beta$ radiation: no observable change With a high-voltage spark ...
9
votes
4answers
921 views

Can we feel heat in outer space? [duplicate]

Is there air outside of earth atmosphere? If not, could we feel heat coming from sun?
0
votes
1answer
45 views

Can heat energy be transferred through matter by radiation?

My hypothesis is that it is not possible for heat to be transferred this way because it seems that any matter would simply experience a temperature increase instead of allowing heat to pass through. ...
2
votes
2answers
133 views

Contradiction about decay constant

According to my textbook: $\text{decay constant } k = \frac{A}{N}$ ,where $A$ is activity, $N$ is no. of undecayed nuclei $ = \frac{\text{no. of nuclei decayed per unit time}}{\text{total no. of ...
0
votes
1answer
40 views

Entropy Change in Radiation and Convection

When a system loses it's internal thermal energy by emitting radiation or by convection what is change of the systems entropy mathematically? I saw this question's answers for radiation only but still ...
-2
votes
1answer
43 views

Relate count rate with the type of radiation emitted

I'm currently studying radioactive decay, and I was faced with a question where the count rate measured (using a counter) was given. With that, I was asked to state what type of radiation is being ...
0
votes
0answers
19 views

Can a nuclear electromagnetic transition rate be affected by the electron configuration (e.g. bare nucleus v neutral atom)? Any experimental examples?

When an atomic nucleus undergoes a transition and emits a gamma ray, the wave function of the nucleus changes, which can result in a slight redistribution in charge. Some electron orbitals have a ...
1
vote
0answers
18 views

Light-driven Carnot engine

Based on the definition of the Carnot engine, it is reversible, runs in a cycle, and is frictionless, which would result in the conclusion that the Carnot engine is the most efficient engine. The ...
0
votes
0answers
18 views

A book for single-photon emission computed tomography (SPECT) physicality

I am a graduate student, and I research the radiation detector which is similar to SPECT geometry. So I need a book to understand the physics inside the SPECT. Could you recommend books that describe ...
2
votes
1answer
32 views

Harmful Radiation When a Thinly-Veiled but Evident Sun is Directly Viewed Under Haze or Cloud Cover

When it is hazy or overcast with many thin fast-moving clouds, the sun sometimes appears faintly though the cover---making it possible to be observed without any discomfort. In fact, one could easily ...
2
votes
2answers
43 views

Direction of Radioactive Emission

Where does the emission of a radioactive material directed at? My intuition and background knowledge would firmly say that it is pointing at all directions outward of the atomic nucleus. But let's say ...
1
vote
1answer
32 views

Transfer of energy from radiated to conducted

Can a CO$_2$ molecule in the atmosphere that has been heated by the earth's radiation, transfer that energy to one of the many O$_2$ or N$_2$ molecules nearby? If so, what is the mechanism?
1
vote
2answers
96 views

Why doesn’t radioactive water emit radiation?

Why is standing by a pool of water used to store radioactive depleted rods safe whereas standing by a radioactive piece of metal is harmful? Why is the water in the second loop of a two-loop reactor ...
1
vote
0answers
25 views

Is 25 $\rm kGy$ measured in Kerma or dose absorbed in material?

I have been reading Trends in Radiation Sterilization of Health Care Products form the IAEA. They keep mentioning 25 [kGy] as the dose needed for sterilization (if you ctrl + f 25 kG you will get the ...
0
votes
2answers
50 views

Is it possible to create a laser in the extremely low frequency radio spectrum?

I have been reading about effort to push lasers into the hard X-Ray and soft Gamma Ray range, been quoted as one of the most important problems in physics according to Vitaly Ginzburg. However, would ...
0
votes
2answers
141 views

What has Euler's number $e$ to do with exponential decay?

I know how to derive the formula for "quantity at time $t$" for some decaying materials. You can see the derivation here. But, what I don't get is that what the number $e$ is doing here? We ...
0
votes
1answer
31 views

Does the equivalent dose of radiation have the same half-life as the radioactive material?

I know that if I have a sample of a certain radioactive isotope with total mass $x_0$, then I can calculate how much of that mass is left after $t$ hours using $ x = x_0 \cdot e^{- \lambda t} $. I ...
0
votes
2answers
49 views

Can we detect the alpha and beta particles using the scintillator detectors?

In the experiment gamma ray detection with scintillators, we can detect the gamma ray particle. Is it possible to detect alpha and beta particle using scintillator detectors. If not then why is so? ...
0
votes
1answer
44 views

What is the fastest heat can travel? The perfect solid heat sink

What dictates the conductivity of heat in an element or medium? Consider the shape, volume, area, and distance heat travels from vibrating atom to atom, not through the excitement of the an atom ...
5
votes
4answers
644 views

Can a single piece of paper really block all non-electromagnetic ionizing radiation?

So in my twelfth grade (about 2 years ago), I had a bit of nuclear physics and in it, we talked about how alpha particles could be blocked by a piece of paper, beta emissions could be blocked by a ...
1
vote
2answers
71 views

Do particle decays with different products have different decay rates?

https://en.wikipedia.org/wiki/Particle_decay#Probability_of_survival_and_particle_lifetime lists the mean lifetime of particles. But particles may decay in different ways, so is the mean lifetime the ...
0
votes
2answers
46 views

Units for distance in the Inverse Square Law

I've looked around quite a bit and can find no definitive explanation of which units to use when utilizing the inverse square (or cube) law. I can find the top level explanation: if you double the ...
6
votes
2answers
517 views

How is the randomness of single atom radioactive decay verified experimentally?

What experimental setups and statistical tests are used to empirically verify that the decay of a single atom cannot be predicted, it is truly random the decay of a single atom is not influenced by ...
1
vote
1answer
24 views

Understanding the determination of Radon activity

When we want to determine the radioactivity of a nucleus, we usually determine the counts detected using say a Geiger counter. The count rate is then usually used as the disintegration rate i.e. the ...
1
vote
2answers
61 views

Can wires related to modems and internet emit harmful radiation?

I am installing internet services at my house and need to run wires (Ethernet, modem, router related) along the lower part of the wall near some beds. Can people sleeping in the beds be exposed to ...
-1
votes
1answer
64 views

Can an aluminium chip with some engravings protect people from harmful effects of electromagnetic radiation? [closed]

I have come to know about a product called E-Guard by a company called QNET. They say that this small device (Just an aluminium piece with laser engravings) can protect us from harmful effects of ...
0
votes
1answer
43 views

A body kept inside a perfectly black body

A spherical body of area A and emissivity e=0.6 is kept inside a perfectly black body. Total heat radiated by the body per second at temperature T is? The options are a.) 0.4 sigma AT^4 b.) 0.6 sigma ...
2
votes
0answers
67 views

Work done by radiation on an electron

I'm studying quantum mechanics (already done with relativity) and I'm trying to understand the matter-radiation interactions. It's said everywhere that matter emits or absorbs photons but nowhere it's ...
1
vote
2answers
49 views

Near field and Far field

in EM radiation, it is generally considered that if $D \ll \lambda$, $D \ll r$ and $r \gg \lambda$, it is radiation zone ($D$ is the antenna's length). I can't seem to see how that fits the Fraunhofer ...
3
votes
1answer
143 views

Is it possible to calculate the acceleration of an alpha particle emitted by a radionuclide?

Is it possible to calculate the acceleration of an alpha particle emitted by a radionuclide, for example Po-210? I suppose the alpha particle appears, after tunneling out of the nucleus, at rest at a ...
1
vote
1answer
52 views

Why is Palladium-108 "theoretically capable of spontaneous fission?"

I was just reading Wikipedia's page on palladium isotopes and I noticed the note about Palladium-108. It says "theoretically capable of spontaneous fission", but I don't find that explained ...
1
vote
2answers
39 views

Does inverse square law indicate beam angle of radiation source?

I was told that the radiation intensity from a particular X-ray machine falls in half every 4 feet. I think this should tell us something about the angle of the beam from the machine. I use ...
0
votes
1answer
44 views

How to produce ionizing radiation without radioactive substance?

I think ionizing radiation caused by ray or particles. My professor told me:"without radioactive substance,with only commercial products,it's possible to produce ionizing radiation." Can ...
2
votes
1answer
43 views

Rutherford's alpha ray scattering experiment

Why didn't the alpha particles collect electrons on their way while penetrating the gold foil in Rutherford's experiment?
1
vote
2answers
45 views

Why is radiation of a particular frequency most intense in black body radiation?

Why is radiation of a particular frequency more intense than other frequencies in black body radiation? Does this mean that most electrons in the object are emitting photons of that frequency? If this ...
0
votes
0answers
78 views

A question on melting ice

I have a question on melting ice using solar energy. Assuming solar energy transfer in ice obeys Beer's law, i.e. $$R(z)=R_0e^{-z/d}$$ then the intensity could be expressed by $$I(z)=\frac{dR}{dz}$$ ...
1
vote
1answer
20 views

What would be the most UV resistant rubber color?

I'm looking for the longest lasting speargun bands. They come in a variety of colors so I'm wondering if a certain color of rubber would help them last longer. They will be exposed to a lot of ...
0
votes
0answers
25 views

First non-unique beta decay transition (parity of the nucleus is changes)

What is the difference in the cross-section of the allowed and 1st non-unique forbidden beta decay transition? In other words, how does the change in parity of the daughter nucleus influence the cross-...
1
vote
0answers
40 views

Estimate minimum mass A of unstable nuclei for $\alpha$ decay

I want to estimate a minimum mass $A$ from which nuclei can be unstable for $\alpha$ decay using the liquid drop model. I started by writing the reaction's Q value for the usual $\alpha$ decay, in ...
0
votes
1answer
63 views

Muons and Electrons Rare Beauty decay

Concerning this recent news from CERN: CERN data on ‘beauty quarks’ behaviour may rewrite physics as we know it (TRT World, 24 March 2021) My son and I (now 13yo) have been doing home based weighing ...
0
votes
3answers
83 views

Why do atoms only absorb energy in the form of radiation or heat?

Why do atoms eject electrons only if they are provided energy in the form of radiation(photons) or heat(thermal energy or friction)? Why can't we excite atoms by increasing its other energies like ...
0
votes
1answer
21 views

Wave/particle duality of an alpha-particle that is emitted by alpha decay

I am wondering about the wave/particle duality of an alpha particle in vacuum. Suppose a U-238 nucleus emits an alpha-particle in vacuum. Is the alpha particle initially a spherical wave propagating ...

1
2 3 4 5
27