Edge Definition and 253 Threads

Homework Statement A 15 kg child stands on the edge of a small merry-go-round of radius 2.0 m. If the merry-go-round turns at a steady rate of 11 rpm, calculate the magnitude and direction of the net force on the child. Homework Equations I'm thinking FG = G(m/r2) The Attempt at...

Let points $A$ and $B$ be given on the plane. The mid point of $A$ and $B$, call it $M$, is also given. Mark an arbitrary point $P$ on the plane. Using unmarked straight edge only, construct the line passing through $P$ and parallel to $AB$.

I'm not a physicist! Just wondering what it is like on the edge of the universe? how many dimensions will be there, what force will be acted upon a close object, and what relativity will become? I'm assuming the universe is euclidian (eucklidean? euclidean? my English sucks.) not hyperbolic or...

Homework Statement An ant positioned on the very edge of a Beatles record that is 14.80 cm in radius revolves through an angle of 70.0o as the disk turns. What is the ant's path length? What is the magnitude of the ant's displacement? Homework Equations L=Rtheta The Attempt at...

Hey there guys, I remembered one stormy night while playing Atari racing game with my son..he asked me: "what is faster force of light?" I escaped with a reply .. "flash first..thunder later" .Suddenly the power was out. My kid went to fetch the flashlight and said to me.."look! push first...

Hello, I am trying to determine the band gap of an amorphous material (a glass sample) and I read that you can do this from the determination of the optical absorption edge. From this kind of measurements you fitt an equation of the type (αhν) = B (hv-Eo) 2. my question are: 1 - is it...

Homework Statement Find the volume of the region D in R^3 which is inside the sphere x^2 + y^2 + z^2 = 4 and also inside the cone z = sqrt (x^2 + y^2) Homework Equations The Attempt at a Solution So I decided that the best approach might be finding the area under the sphere and...

http://community.accelrys.com/servlet/JiveServlet/showImage/2-14223-12512/%E5%9B%BE%E7%89%871.png I want to assign displacement to the top edge of the above model in Material Studio. How to realize it ? Thank you !

Homework Statement A long cylindrical insulating shell has an inner radius of a = 1.37 m and an outer radius of b = 1.60 m. The shell has a constant charge density of 2.70 10−9 C/m3. The picture shows an end-on cross-section of the cylindrical shell. What is the magnitude of the electric...

I was having a discussion with someone far more expert than I and for whom I have a lot of respect. He was telling me that the path loss of a radio signal from A to B is not necessarily the same as it is from B to A. One of the reasons he mentioned is diffraction over a knife edge which in...

So here is the problem I have. There is a box that is 27.5" tall and 41" tall with a mass of 480lbs. One edge is put on a 3.5" tall block while the other is raised 12" and dropped. The question is to see if the block will continue to rotate and fall on it's side. I have been able to find the...

We are often told that to understand why the universe does not have an edge think of it like the Earth which has no edge. But I think this analogy breaks down because you can escape from the Earth's gravity and enter into outer space, plus you can dig into Earth and theoretically come out the...

I am having difficulties with this question as no height for the crater is given please help! :) Homework Statement AN astronaut is speeding over a level stretch of the Moon's surface at 12m/s in her small lunar rover. She drives over the edge of a crater, whose surface slopes downwards at an...

What is an "Active*low*Input*and edge* triggered input?" I have been reading up on Flip Flops but can't find anywhere that explains in simple terms what an Active low input and edge triggered input are. Can someone help me understand it please? Thanks

First off let me state that I'm just a mechanical engineering student, so I'm not too savvy when it comes to quantum physics, but my teacher was talking about this equation in class and it reminded me about infinite wavelengths near the egde of the universe and the event horizon on a black hole...

Prove by induction on the number of edges in a graph that any bipartite graph has edge colouring number equal to its maximum valency. Also, Find such an edge colouring for a bipartite 4-regular cartesian or tensor product of your choice of 2-regular graphs

I've been mauling some questions about the end/edge of our universe in my head over the last couple hours, and Google is soooo inundated with useless pages. So I figured I'd come here to get some theories. Sorry if I ask any dumb questions or posted this in the wrong thread. To Mod- I will move...

HI , i am a student currently in class 10th , and i aspire to become a theoretical physicist . I particularly want to know about the edge of the universe when i become one . Any way , i have searched the net for many years of posts related to these topics , but most of that stuff is above me ...

Here's my current project goal ( And what I need help with): I want to use an LED light source, shine it through a 1" x 2" slit and then use a linear array camera to detect the edges of the slit. The problem: Since LEDs are a point source of light emission, my camera has a difficult time...

Homework Statement mmouse = 0.06kg r = 0.3m \omega = 0.05 rad / s Suppose angular speed does not change. What is the work needed for the mouse to go to the center. Homework Equations Io\omegao = If\omegaf The Attempt at a Solution If \omega doesn't change ,then how can...

I've looked everywhere and can't seem to find any information. Would someone be kind enough to point me to some literature?

Folks, I'm self-taught and am currently trying to get up to date about the newest developments in field-emission microscopy and other methods of imaging sub-atomic structures. I'm able to follow (though just barely) Mikhailovskij et al.'s 2009 paper in Physical Review showing electron orbitals...

I was just thinking. If I would have particle and an interface behind which there is zero proability of this particle being there, what would happened if I tried to push it over this boundary? It will bounce back, spread along this boundary or happily went into oblivion pretending that it...

First post in the Physic forum, the thread title are the words that really get on my nerves. I have the following questions. a) Cosmologists say the universe started at a singularity, there for there is a point where the universe started to expand from, if you could look at the singularity...

Consider a function Q, from some set D in R2 to some set in R3. Suppose Q parametrizes a surface S. Orientation of the edge of the surface must be compatible with orientation of the surface. I read that if the parametrization of the Boundary of the domain D give it anticlockwise direction...

If we are not located at the center of the universe, then when we look out into space are we not sometimes looking towards the center of the universe and at other times towards maybe the edge of the universe. Assume the universe is finite- since we put an age on it, and the fact that it is...

Homework Statement Two children stand on the edge of a merry-go-round while their friend accelerates them to an angular speed of 3 revolutions per second. The merry-go-round has a radius 10 m and a mass 100 kg and both kids weigh 35 kg. Once they reach this speed one of the kids jumps off...

Overview I've been struggling at this problem for about 3 days now. I've posted it on a couple forums will no answers, so maybe I'll get a solution here. Thanks in advance! Plain Diagram: http://www.swivelgames.com/projects/ideas/circlepoints/getseglength_simpler.png Known: A, B, C...

Homework Statement The Attempt at a Solution Based on my attempt above, I have demonstrated that the order is less than or equal to n. I am certain that it is actually n, but I'm not sure which theorem I can grab finish this thing off. Any tips for pointing me in the right direction?

Hi guys, I am really stumped by this 1st yr Dynamics question, and would appreciate any help on how to approach the question. Homework Statement Homework Equations Torque equations and Force equations Moment of inertia for disc rotating around centre: (mr^2)/2 After using parallel...

Homework Statement A 17 g bullet traveling 475 m/s strikes a 0.7 block of wood that is balanced on a table edge 0.7 m above ground. If the bullet buries itself in the block, find hte distance D at which the block hits the floor. Diagram: Homework Equations Wnc = delta KE + delta PE...

http://www.bjmath.com/bjmath/probable/flips.htm http://en.wikipedia.org/wiki/Feller's_coin-tossing_constants In the above 2 links, it's mentioned that if we toss a fair coin ten times then the exact probability that NO consecutive heads come up in succession (i.e. n = 10 and k = 2) is p(10,2)...

I got a problem that I need to figure out. I have a piece of pipe 20 inches long and I bend it on a radius at 90 degrees. I measure from the back of the pipe to the end of one side and get 9, I flip it the other way and do the same thing and get 13.555. If you add those you end up with a...

Homework Statement I attached the drawing. The force of magnitude F acts along the edge of the triangular plate. Determine the moment of F about point O. Homework Equations M=rxF The Attempt at a Solution What I did was I just picked the top left point of the triangle and labeled...

What do you think about the feasibility of adding leading edge slats to a hang glider in order to reduce the stall speed and increase the wing loading. I've seen charts showing nearly a twofold increase in the achievable coefficient of lift because the angle of attack can go so much higher...

My friend was telling me about something he read about involving points on a circle that seemed kind of cool. It went something like this: Have a circle of radius 1, and mark n equally spaced points on the outer perimeter. Choose one of the points, and connect all other points to it...

I am wondering about the size of the universe. I have read that we can only "see" 13.7 billion light years away in all directions and that we are in the center. To my mind this presents a problem. The problem is what are the odds that we are in the center of the universe? Then again even...

Does anyone know how to determine the leading-edge radius of an airfoil using just the x y coordinates.

This article http://www.physorg.com/news/2011-06-big-edge-solar.html" tells about discovery of magnetic bubbles at the edge of solar system. As I understand they are around 100AU from Sun and around the size of 1AU. That makes them roughly 3.6° angular size. Shouldn't these bubbles cause...

Voyager discovers magnetic bubbles or a magnetic foam at the edge of the heliosheath. http://science.nasa.gov/science-news/science-at-nasa/2011/09jun_bigsurprise/ Is this new physics being discovered?

Since we know that Information gets more and more dense the slower time gets, and that if you were to slow time to less and less units of time, than exotic particles will start forming and annihilating each other completely randomly (known as the Heisenberg's uncertainty principle), than I...

Hello, I am trying to understand an equation stated in the book 'Principles of Protein X-Ray Crystallography' by Jan Drenth (The exact page I am reffering to can be found here...

I believe that the edge of our universe is within our reach because the only way that i see disproves this is for inflation to be faster than light. As this might cause trouble with time, I think that that's the only explanation. If you assume that there's a center, than the edge must be within...

I am self studying physics, and a problem that I have not been able to figure out has been bothering me. Look at the image (also attached): http://imgur.com/xHP2S" Let's say that the side length is 1 m. and the mass is 10kg. The object has no initial velocity and assume there is infinite...

Hi, could someone tell me how the fine edge structure next the the absorbing edge in an XAS arises? from my understanding an XAS is a plot of absorption coefficient against energy of incoming xray. The absorption edge is at an energy corresponding to when the energy is just sufficient to...

Does it make sense to say that the universe has an edge/boundary? Neutrinos are moving all the time with practically no interaction i.e., unimpeded. Where are these reaching after a very long time (t->infinity)?

Hello everybody. Im starting a project on the basic processed undergoing in the edge plasma region. ( I mean, near the walls of a plasma confining device, like a tokamak or so.) I was wondering if you could name some ''things'' I should be aware of in order to make a small PIC code or...

Homework Statement a worker on the roof of a building that is under construction dropped a 0.125 kg wrench over the edge. another workman on the 8th floor saw the wrench go by and determined that its speed at that level was 33.1 m/s. the first floor of the building is 12.0m high and each...

I had been reading several articles on topological insulators (TI) including the Kane and Hasan's 2010 RMP. I am not very much clear about the Z_2 invariant TI. I mean, the even-odd argument proposed by Kane and Male (also argued by S. C. Zhang's group and Joel Moore's group in a different way)...

Does anybody have any experimental data on flat back airfoils. I would like to know the experimental data, experimental setup and initial flow parameters etc. In case if you find it from a report I would be glad if you can give some information regarding the report, such as author, report name...