Cloud Definition and 256 Threads

I've built a simple cloud chamber using a peltier cooling element and I'm able to see some tracks which is really exciting. But now I've seen in many places that you can apply a high voltage between the floor and a ring at the top of the chamber to further improve sensitivity, and also to force...

problem: The radiation from an old evolved star of radius 10^6km is obsorbed by a spherical dust and gas cloud, ejected previously by the star, of radius 4*10^8km. If all the radiation from the star is re-emitted by the cloud, which is observed to have a temperature of 500K, what is the...

What exactly is a "radiation cloud", as mentioned currently in the news, in a physics sense? Is it just a bunch of super excited water vapor? Is it actually radioactive isotope particles? How stable is it? I can't seem to find any info on the term.

Hi, I had a previous post "Total Energies" asking about the total energy of an electron and proton separately in a "stable," ground state, hydrogen atom and I got no response (well one short one). Later I realized an isolated hydrogen atom is not stable; it at least needs to bond into H2, but...

Interesting question to think about. We know that there are lots of comet bodies in the Oort cloud and we know that even in the near absolute zero temperatures evaporation does take place. Comets are usually covered in dust, which slows down this evaporation, but let's consider clear body...

What is the largest astronomical body in the Oort cloud? Do such clouds exist for most solar systems?

Homework Statement A star of mass M and radius R is moving with velocity v through cloud of particles of density \rho . If all the particles that collide with the star are trapped by it, show that the mass of the star will increase at a rate \frac{dM}{dt} = \pi \rho v \left(R^2 +...

Homework Statement Beginning with \frac{d^2 r}{dt^2} = -G\frac{M_{r}}{r^2} , adding a centripetal acceleration term, and using conservation of angular momentum, show that the collapse of a cloud will stop in a plane perpendicular to its axis of rotation when the radius reaches r_{f} =...

Homework Statement To show how conservation of angular momentum applied to to a collapsing MC core implies flattening during cloud collapse consider the equation of motion of a parcel mass m in a rotating initially spherical cloud of total mass M, initial angular speed w0 and radius r0...

Note: this is one of the suggested practice problems for my second-year classical mechanics course. Homework Statement A spherical asteroid of mass m_{0} and radius R, initially moving at speed v_{0}, encounters a stationary cloud of dust. As the asteroid moves through the cloud, it collects...

Homework Statement A spherical asteroid of mass m0 and radius, R, initially moving at speed v0, encounters a stationary cloud of dust. As the asteroid moves through the cloud, it collects all the dust that it hits, and slows down as a result. Ignore the increase in radius of the asteroid...

Me and a friend at school have been thinking about this question for a while and have come up with a few perspectives, I'm sure there's a 'proper' answer but I haven't managed to find one even after scouring numerous web pages. We are aware that the electron doesn't 'move' in a sense, only the...

I am sure to those of you who know GR this will be a simplistic question. I can only hope there will be a simplistic and definitive answer :-) Assume a dust cloud of radius=5 and a mass =mc ANother equivalent mass of condenced matter md=mc with a radius=1 What would be the...

Voyager 1 launched in 1977 is ~10^10 miles out, near heliopause. Continuing at it's current velocity (3x 10^8 mph), for 3300 yrs (100x current 33 yrs), then it will be out ~10^-2 lyrs; that is approaching Oort Cloud outer gravitation limits of our stellar system...

What caused the ring around the atomic mushroom in Nagasaki?

Homework Statement Assuming the maximum electric field sustained by dry air in a cloud is 3x10^6 Vm^-1 And a distanceof 1000 meters between Earth and cloud. The cloud is 4km long and 1 km wide. ausume uniform eletric field. Find the potential difference. Homework Equations V=Ed \mu =...

Homework Statement when a charged particle enters a magnetic field in a cloud chamber, why does it move in a circular path instead of straight line? I have no idea why. please help Homework Equations The Attempt at a Solution it has something to do with the r changing? as I said...

Last week there was a documentary program on Nat Geo I believe having to do with the composition and origins of comets. The narrative seemed to imply that comets originate within & are rather randomly dislodged from a spherical shell around the Solar System called the Oort cloud. This...

An alpha-particle produced by radioactive decay leaves a visible continuous track in a Wilson Cloud Chamber. As it collides with and ionizes the molecules of the vapor, its position is constantly being “measured” by the vapor molecules. If a magnetic field is present, its track will be curved...

An interstellar gas cloud can be roughly described as spherical with a uniform density. Its radius is R and its total mass M. By considering the gravitational potential energy of a thin spherical shell, show that the total potential energy of the cloud is given by...

Lately I've read some articles about the possibility of a Jupiter-sized planet hidden in the Oort cloud. This assertion is based on analysis of cometary deflections and observations of Sedna. What is the likelihood of this? We all know that there must be lots of planet-sized stuff out...

in the electron cloud model is the electron cloud where you would most likely fin the electron at?

Atom orbitals, I mean the ones where electrons orbit proton with continuous trajectory like planets orbit around the sun. I do not mean to disagree with modern teachings nor to speculate, I simply do not see how QM actually excludes this possibility. I just want someone walk me through several...

OK I know many people here are familiar with cloud chambers particularly those of you who are teaching. I have never built one but I want to go all out on my first attempt. I have seen plenty of instructions from researching through google and I was wondering if you guys have any additional tips...

Homework Statement In a typical lightning strike, 2.5 c flows from cloud to ground in 0.20 ms. What is the current during the strike? Homework Equations I = Q/t The Attempt at a Solution The reason I keep getting this wrong is because it says I am rounding something off wrong. I...

Homework Statement one cubic centimeter of a typical cumulus cloud contains 50 to 500 water drops, which have a typical radius of 10 micrometers. for that range, give the lower and higher value, respectively, for the following. a) how many cubic meters of water are in a cylindrical cumulus...

Homework Statement Consider a uniforms cloud of density ρ1 which consists of many little drops that are approximately still.Consider a special rain drop that is a little more bigger than the others so that it starts to fall down.Water drops stays spherical all the way.But the radius gets...

I often hear that stars form when giant clouds of hydrogen start to collapse under gravitational forces, so I started thinking about this. Gravity depends on the masses and distances of objects. So how many atoms of hydrogen would you need, and at what average distance would the atoms need to...

1.A cloud of neutral hydrogen is moving towards us at a speed of 70 kilometers per second. At what wavelength would one observe the radio spectral line characteristic of neutral hydrogen? 2. The filament in a regular incandescent light bulb reaches a temperature of 2900 k when it's on. a...

Assuming we have 3D clouds at time t1 and t2 in the same area, I'd like to discuss you about the idea moving cloud between two different times. (just in simulation) http://www.freeimagehosting.net/uploads/f7d37951ba.png (there is no any parameter, only cloud volume in the each position)...

Homework Statement A very short pulse UV laser is used to liberate a number of electrons from the negative plate in the arrangement in (i) above. The electrons drift towards the positive plate under the influence of the electric field over a time scale much longer than the laser pulse...

Homework Statement draw the field lines of a simple hydrogen atom model. A case is given where a proton is surrounded by an electron cloud. Without getting into quantum mechanics how would represent the field lines of this mini sphere inside and out. Homework Equations gauss's law The...

Homework Statement A spherical asteroid of mass m_0 is moving freely in interstellar space (no external forces) with velocity v_0 . It runs into a dust cloud whose uniform density is \rho_d Assume that every particle of dust that hits the asteroid sticks to it and that the asteroid remains...

http://www.lns.cornell.edu/~adf4/cloud.html" Has anyone tried this? It looks really cool, and I am thinking about giving it a shot, but I'd like to know how easy it is to get it working, or if there are any other things I should know. One thing I am concerned about is the directions say...

At higher altitudes in the atmosphere, why do aircrafts (particularly fighter aircrafts) with jet engines leaves some kind of white cloud trailing behind? It doesn't disappear for a reasonable amount of time. What is this? Thanks!

I've been trying to massage my data into a usable form for a while now and thought I'd consult the brain trust. I have a triangular mesh that represents the surface of an embryo. I also have a (x,y,z,c) point cloud near that surface where c represents a protein concentration (proportional to...

Cosmic Cloud Poised to Birth Massive Star http://www.space.com/scienceastronomy/090609-aas-massive-star-precursor.html Ref: http://news.yahoo.com/s/space/20090609/sc_space/cosmiccloudpoisedtobirthmassivestar A sleeping giant http://www.astronomy.com/asy/default.aspx?c=a&id=8340 The...

Homework Statement Consider an HI cloud of temperature T ≥ 3 K. a) Calculate the energy level difference between the hydrogen atom states leading to 21cm line emission. Show that the ratio of hydrogen atoms in the upper to the lower state of the 21 cm line is approximately 3:1. b)...

Problem:"An interstellar cloud with a radius of 10parsecs and a mass of 10000 Msun is contracting. How long does this take? (The cloud itself has no pressure)

This is my first post here, so I'll start off by just saying hi. ^_^ Anyway, I've been in a debate recently with somebody at another website and some interesting topics have come up that I would like to learn more about. The person I'm in the debate with clearly doesn't understand basic...

The Titus-Bode law (and Dermott's Law) hypothesizes resonances in certain orbits. In general, in our solar system, each planet is roughly twice as far out as the previous planet. This also seems to hold true for moons around their parent planets. 5.2 AU - Jupiter 9.5 AU - Saturn 19.2 AU...

One cubic centimeter of a cumulus contains 330 water drops, which have a typical radius of 10 μm. (a) How many cubic meters of water are in a cylindrical cumulus cloud of height 2.9 km and radius 1.0 km? (b) How many 1-liter pop bottles would that water fill? (c) Water has a density of 1000...

One cubic centimeter of a cumulus contains 330 water drops, which have a typical radius of 10 μm. (a) How many cubic meters of water are in a cylindrical cumulus cloud of height 2.9 km and radius 1.0 km? (b) How many 1-liter pop bottles would that water fill? (c) Water has a density of 1000...

regarding probability clouds: if there is a charge cloud surrounding a particle then could there also be a mass cloud surrounding it? the charge cloud would rotate producing a magnetic moment and the mass cloud would rotate producing angular momentum. both would spin at the same rate but...

An electron enters a cloud chamber which has a magnetic field B but the path of the electron is not perpendicular to the magnetic field. I understand that the electron path will describe a spiral. Does the v in the equation F = q(v x B) refer to the component of the electron's velocity which is...

This article just showed up today about the blonde haired, white skinned nation of people called the Cloud People or Chachapoyas. The site is reported to be about 4.2 hectares in size. What drew the people that found the site to it was the sound of an enormous waterfall they found to be 500...

Here's a picture of it http://www.nasa.gov/mission_pages/cassini/multimedia/pia09188.html I found this very striking and am surprised that there has been so little talk about it. My best guess is that it has something to do with tidal forces being exerted by multiple moons. I'm...

Hi all, Does anyone know if there is a recent table of the abundances of elements in the Small Magellanic Cloud. Thanks all

I've read that cosmic rays are far higher energy than those generated in manmade particle accelerators. Would it be worthwhile to build an orbiting cloud chamber to collect cosmic rays before they impact the Earth's atmosphere? Or would the collision rate be too low to provide statistically...

This promises to be a very difficult final round. You have one vote to cast on the picture that best represents our theme - clouds! 1. hypatia 2. Alex:) http://img224.imageshack.us/img224/5396/mousilaukecloudug1.jpg 3. Andre 4. Borek 5. Air 6. larkspur...