Scale Definition and 721 Threads

If you stand on a bathroom scale, the spring inside the scale compresses 0.50 mm, and it tells you your weight is 740 N. Now if you jump on the scale from a height of 1.2 m, what does the scale read at its peak? I'm guessing you use 1/2kx^2 but otherwise, I'm not sure.

Hi! I'm making a computer program that represents some quantities in a graph in this way: x'i=(xi-xmin)/(xmax-xmin) so that the possible values of x range from 0 to 1. This is a linear scale. I want to do the same with the logarithmic values of xi. That is, I want to implement a log...

Understanding the short-distance behaviour of gravity is crucial for constructing a quantum theory of gravity. The Newtonian inverse square law approximation has been tested in laboratory down to millimeter scales, but I'm not aware of any laboratory scale experiments testing general...

Hello, I did a wind tunnel test of a rectangular box with equal sized louvered window at the inlet and outlet. This box is a scale model and representative of a typical room with windows for cross-ventilation. I measured the velocity inside the room. Now I want to calculate the Reynolds...

Homework Statement the gas scale temperature is defined as: T=273.16 lim Ptp->0 (P/Ptp) The bulb of a constant volume gas thermometer is immersed in an ice-water-vapour mixture and the recorded pressure is 0.500 atm. It is then immersed in a boilng liquid and the pressure is 0.720 atm...

Hi all, I am about to begin my studies as an experimentalist and I keep hearing about these terms when someone represents his data as histograms. Can some one here, please, give me a clear explanation about their meanings. My background is theory and you can use as much mathematics as you...

I was going through few books and i found out that piezoelectric concept generates good amount of current but not enough power(wattage) ... As I was thinking of making a project on this concept can somebody tell me how can huge amount of voltage as well as current be generated from piezoelectric...

I know because E=(n+1/2)*h-bar*omega , and n is an integer , with the integers ranging from zero, to all positive values. Photons are said to be massless physical quantities and according Einstein's theory of special relativity (or general relativity) mass and energy are equivalent. So if a...

Planck energy: E_P = m_P c^2 = \sqrt{\frac{\hbar c^5}{G}} Gravitational radius: r_G = \frac{r_s}{2} = \frac{G m_P}{c^2} Gravitational radius is equivalent to Compton wavelength: r_G = \overline{\lambda}_C \frac{G m_P}{c^2} = \frac{\hbar}{m_P c} Planck force is a constant in the Einstein...

Hello! If I have the gaussian function, but x is a loarithmic scale. Can I infer that, if x was plotted using a regualr scale, that the function would be 'fairly' linear? At least initially? As the rate of change gradually increases befor slowing down again. I think this is reasonable... I...

In the movie Speed a speeding bus is shown jumping a long gap in the elevated freeway. The Mythbusters test the physics at 1/12 scale. In the TV show Grant writes an equation to find the scaled down ramp exit velocity, where supposedly one must compensate the small scale speed downward because...

Could someone explain the relationship between the FSC and the Planck Scale? What are they in relation to each other. I know what the Planck Scale is, and I even have a loose understanding of the FSC, but what of them in contrast and comparison? And how does the FSC affect QM, if at all...

Hello All, I'm currently working on a project to help with a local spaghetti bridge contest. I'm trying to build a scale of sorts from a plate that is supported at each end. Picture a bracket "[" but with the two legs on the ground. I'm using strain gages on the bottom in the shape of...

Hi I have to perform a fitting procedure on a semi logarithmic scale but I'm not sure how to weigh the experimental data points. I'm studying the decay of the luminescence of a certain type of crystals and the function I'm using has the form I = \frac{1}{\tau} e^{-\frac{t}{\tau}}...

hi, if we drop a piece of meat say 1kg from 1m above the plate, on a plate 2kg, and the plate is on a weighing scale of spring F=kx, how do we find how much the spring will first compress? ( not referring to the equilibrium where total weight = spring force) so we can't use F=kx = mg here...

So whose quantum gravity theory will crash-and-burn if this is correct? http://physicsworld.com/cws/article/news/40834 Zz.

Um, I suppose this is very basic but I just got kind of confused. Okay suppose you are standing and swinging a rope with a mass attached to its end, so that the circular trajectory of the mass at the end of the rope lies in a vertical plane. And suppose you are stood on a weighing scale. Does...

Homework Statement I want to try to find the scale height of a planet using H=kT/Mg, where H is the scale height, k is the Boltzman constant, T is the surface temperature, g is the acceleration of gravity, and M is the mean molecular mass. I am having a great deal of trouble understanding...

Hello, I have been trying to make a parametric plot with logarithmic axes in Mathematica, but have been unable to find an option to do this. Can someone tell me how to do this? My code is below, and for reference, EnergyScint[b] is the Bethe-Bloch equation for energy deposit for a fully...

Hi, I would like to know something about the possibility to convert data set into z-scores to ensure a common scale for analysis. More specifically, when this conversion is needed and why. I am working on motion data (from 3 persons) tracked from video and I can use a common reference for...

Homework Statement You use a spring scale to pull a 1.5 kg object on a horizontal frictionless surface with a constant horizontal force of 1.3 N (according to the scale reading). You use a stopwatch to time how long it takes the object, starting from rest, to cover a distance of 2.7 m. What is...

I want to create a plot, but want the horizontal axis to have increments as multiples of pi eg. {0, pi/2, pi, 3pi/2, ... } Is this at all possible in matlab?

Hi, I'm currently looking into reflectivity and emissivity of metals in sunlight. However, I can't quite grasp how the mechanisms of reflection and emission differ. Emission obviously occurs because an electron is exited by a photon and then is de-excited and emits photon or photons. However...

Homework Statement Let's say you are given 10 identical springs. How would you develop a scale of force (i.e., a means of producing repeatable forces of variety of sizes) using these springs? Homework Equations None that I can think of. The Attempt at a Solution My guess is that...

Homework Statement Hi guys, I have a question on problem 4.11 in Kleppner and Kolenkow's mechanics book. A chain of mass M and length L is suspended vertically with its lowest end touching a scale. The chain is released and falls onto the scale. What is the reading of the scale when a length...

http://img233.imageshack.us/img233/5816/espaotempoquntico1.th.jpg Two pictures of quantum spacetimes... The theory of quantum gravity (LQG) can perform calculations and predictions on the concrete structure of space and time at the Planck scale. Equations formulas that describe...

CMB fluctuations and large scale fluctuations nowadays do not match ? The CMB dark matter density fluctuations for big scales is d_rho/rho~ 10^-5 and lower. The scale factor increased ~ 1000 times from last scattering to now. Linear perturbation theory predicts that the density fluctuations...

In his book THE BLACK HOLE WAR, 2008, Leonard Susskind makes the following comments around page 135-137: In the following he happens to be referring to a Planck scale cube...let's ignore that specific geometric shape... (Later in the book of course he describes his holographic...

Can you think about relativity in terms of the motions of atoms as they are subject to intermolecular forces? Is time moving slower for the atom which is accelerating with respect to another? Or, would the macroscopic averaging negate the individual motion of the atoms? Or, is this a...

Homework Statement Give an argument for there being a connection between scale length and frequency Homework Equations scale length = (wave length) / (Length)The Attempt at a Solution So from only my physical intuition I'm coming up with the longer the scale length the longer the wave length...

I don't quite understand why macroscopic objects we encounter in everyday life don't exhibit quantum probabilistic behavior. For example, the car standing in front of my house has a definite position and definite boundaries rather than being dissolved in some cloud where it's not clear whether...

Hello all! I'm a sophomore in college and the only real lead I have so far is becoming a teacher. I had an awesome high school physics teacher and decided during my freshman year in college that I want to teach college physics. Currently, I'm on track for a B.S. in Physics. Further on I plan to...

Homework Statement A beaker with water is in equilibrium with a certain weight in a balance. Then we tie a cord to a stone, and soak the stone in water, without touching the bottom. What will the balance read and why? http://dl.getdropbox.com/u/698994/ilustra%20forums/experiencia%20empuxo.png...

http://www.boingboing.net/2009/08/01/bobby-mcferrin-hacks.html" Many of the comments below the video and on other websites point out that it is pretty incredible that the audience knows the pentatonic scale and easily follows what McFerrin wants them to do. McFerrin, at the end of the video...

The major conclusion: “A link between the Sun, cosmic rays, aerosols, and liquid-water clouds appears to exist on a global scale…” http://docs.google.com/gview?a=v&q=cache:k3yiHsNVc1cJ:www.wzforum.de/forum2/file.php%3F0,file%3D11877 keep in mind that solar modulation of clouds of even 2-3...

Thermodynamics makes good predictions for macroscopic experiments, but the actual physics is going on in the microscopic particular level. The second law of thermo is often thrown around, usually by people who couldn't explain F=ma back to you. My question is the way the second law...

http://www.ift.uni.wroc.pl/~planckscale/movie/ The first one I intend to watch is Steve Carlip's He is talking about similarities that have emerged among different approaches to QG. In particular evidence for reduction of dimensionality as you zoom in (inspect the spacetime geometry at smaller...

Homework Statement If you stand on a bathroom scale, the spring inside the scale compresses 0.55mm, and it tells you your weight is 760N. Now if you jump on the scale from a height of 1.3 m, what does the scale read at its peak?

[FONT="Arial Black"]This is not homework, but the question is really bugging me. http://answers.yahoo.com/question/index;_ylt=AvTARlSwKz9P_4km_gmMkfTsy6IX;_ylv=3?qid=20090713211453AAIVYtd" Here is the problem: On a scale, you place a glass of water and a ball on each side of the scale. The...

How to convert a continuous inverse scale parameter into a physically relevant quantity: 1) What is a CISP, and why is called continuous and why inverse? 2) how do I deal with it: Example: On http://www.apec.umn.edu/faculty/gpederso/documents/4501/risk45DistFunc.pdf the error function is...

I was hoping some chemical engineers with experience couuld offer assistance on a question about scale/schmoo. I am working in a oil field to determine the best recipie to clean our main water injection lines which have been restricted over the years. A chemical analysis on the stuff shows that...

Has the energy scale (or cutoff) at which the electric charge goes to infinity (the landau pole) been calculated? I sometimes hear that QED has been probed to tiny distance scales, and I was curious how far away we are until we get to distances corresponding to the Landau pole, after which we...

Jose Figueroa is in the Math Physics group at Edinburgh and his research centers on string and susy: http://www.maths.ed.ac.uk/~jmf/ There was a big conference in Poland just now (ending today 3 July) which was interesting partly because it was mixed. Stringers gave talks alongside nonstring...

I'm not sure where to put this post, but it has related to relativity somewhat, so I posted it here. The question I have has more to do with philosophy of science. Anyway, according to Newton's, p = mv, F =dp/dt = ma. But according to Special Relativity, p = γmv , F = dp/dt = γ3maparallel +...

Nanotechnology, is a study of the control of matter on an atomic and molecular scale right? I'm currently studying taking this course in my college and I'm wondering if Nanotechnology plays a part in researching cancer cells. Does Nanotechnology helps in treatment of cancer cells? If...

I keep reading that the energy scale of inflation is possibly 1024eV, while the energy scale of dark energy is around 10-3eV. What exactly are these scales referring to? Is it the energy required to accelerate the universe at the corresponding rates of acceleration? What...

Hello MechEs (or anybody else who'd care to reply) I'm about to get a small, but fairly sensitive analytical scale recently (down to 0.01 mg) and now I'm trying to figure out a way to dampen ambient vibration from the room and its surroundings (people walking around, HVAC, etc.) I've got a...

Homework Statement A 3.0 kg object rotates on a circular platform 1.5 m from the center. The tangential velocity of the object is 10.0 m/s. If the mass is attached to a spring scale, what force will the scale read? Homework Equations Sorry I have no idea. The Attempt at a Solution...

Is anyone interested in going through Hawking and Ellis' book by the title above and posting questions and insights? My interest is in singularities in higher dimensional spacetime, and whether there are other ways to achieve singularities (and their zoology) besides large enough mass. I am...

The slope of the primordial power spectrum (the power spectrum of density fluctuations produced by inflation in the very early Universe before it had been modified by gravitational/hydro dynamics) is often written, P(k) = A * k and then in the same line referred to as scale invariant or the...