Physical Definition and 1000 Threads

Homework Statement The dissolution of 5.25 g of a substance in 565 g of benzene at 298 K raises the boiling point by 0.625°C. Note that Kf = 5.12 K kg mol-1, and Kb = 2.53 K kg mol-1, and the density of benzene is 876.6 kg m-3. Calculate the freezing point depression, the ratio of the...

Homework Statement (2xy-5)dx+(x^2+y^2)dy=0, y(3)=1 (2x+y^2)dx+4xy dy=0, y(1)=1 x^3y'+xy=x, y(1)=2 y'(t)=-4y+6y^3 We're doing these in 2nd yr engineering Math and I have heard the Lecturer say they are useful across all disciplines. I've heard him suggest RLC circuits, springs with...

1. A 17.7 kg block is dragged over a rough, hor- izontal surface by a constant force of 187 N acting at an angle of angle 33.6 above the horizontal. The block is displaced 46.5 m and the coefficient of kinetic friction is 0.199. Find the magnitude Work done by the force of friction...

Hi all, I'm looking to control two outputs using (3) 12 V coil relays, with the SOP of the truth table listed as below: A' B C' + A' B C simplified to: = A' B ( C + C') = A' B ----> Y0 A B C' + A' B C' simplified to: = B C' (A + A') =B C' ------> Y1 The problem I am having is...

Hi, Hopefully this should be a simple and quick question. I've seen many calculations done with \hbar = 1. If I want to convert back into physical units, what is the corresponding transformation? I know wiki gives a description of...

hi guys,does anyone knows what is the physical interpretation of second(third, fourth,...) derivative?

We did an experiment using the physical pendulum to measure gravitational acceleration g. A graph is shown in this link: http://i593.photobucket.com/albums/tt20/omicgavp/measuringggraph.jpg" A nonlinear (possibly chaotic) trend can be seen in our graph even though we assumed small-amplitude...

Are they different in any significant ways? Are they frequently confusing? For whatever reason, I find pchem books somewhat hard to read (for now) because something with the notation is confusing me. Statistical Mechanics books are much more readable. Okay, for some reason, I understand things...

How would you describe the intersection between phase space and space-time?

Homework Statement This problem I have been set is to find real life applications of divergence theorem. I have to show the equivalence between the integral and differential forms of conservation laws using it. 2. The attempt at a solution I have used div theorem to show the equivalence...

Hey all, My question pertains to interior metrics, for example the Schwarzschild interior metric given in post #5 of https://www.physicsforums.com/showthread.php?t=323684 The radial derivative of the first term, the dt^2 coefficient, matches the radial derivative of the Schwarzschild...

The difference between Enthalpy and Heat transfer is the term [FONT="Book Antiqua"]vdP as [FONT="Book Antiqua"]dH-dQ=vdP What is the physical significance of the term [FONT="Book Antiqua"]vdP? :rolleyes: Wherever an article describes the difference between enthalpy and heat transfer, it is...

Hello all, I am new to these forums and just registered. I plan to be an active participant on here and reciprocate the generosity I've observed in other threads. Im looking for a certain "material" that can satisfy this list of criteria that I've put together. I'm pretty sure that I am...

Warning: I'm not a practicing chemist. Answers in as-simple-as-possible language (but not oversimplified!) would be greatly appreciated! I'd like to know if the chemical properties of a solid can be affected by conduction band electrons. I assume that, in the majority of cases (and perhaps...

What's the difference between a physical Law and a physical theory? thanks

Homework Statement A pendulum is constructed using a thin rod (m1 = 2.0 kg, L = 1.0m) and a uniform sphere (m2 = 1.0 kg, R = 0.50 m). The period in "s" for small oscillations is: a) 1.5 b) 1.7 c) 2.0 d) 2.2 e) 2.5 Homework Equations T = 2pi *sqrt(I/mgd) The Attempt at a...

I have a Question: When the imaginary unit, i, is factored with time, t, in the Lorentz Transformation, or when the Hamiltonian is factored (as when Dirac created his Creation and Annihilation Operators,) and i is factored with the momentum, p, the iFactor is always factored with time, energy...

It seems like a problem that a physicist would need to solve, but I can't wrap my head around the physical interpretation of it. http://exampleproblems.com/wiki/index.php/CoV7 Also, why do they use u=c*x2? What is c in this case? It says "classical" so it can't be the speed of light, right?

Homework Statement What are the energies and wave functions for the quantum mechanical model where V = infinity for x less than or equal to 0 and V = kx2/2 for x greater than or equal to 0? Homework Equations 1-D particle in a box E = (h2/8m)(n2/L2) Harmonic Oscillator E = (v +...

Hello, I have recorded voltage signals (in the time domain) using standard electrophys amplifiers. The voltage is that of an electrode inserted in a plant stem as charged objects are brought close to, then into contact with the flower. I was wondering about the significance of the time...

Hi guys. What is really the need for complex numbers? Is there any physical meaning associated with it?

Homework Statement Can this function be a wavefunction of a physical system with finite potention energy: \psi(x)=\frac{A}{\sqrt{x^2+b^2}}Homework Equations noThe Attempt at a Solution The ans is YES. 1)it is continuous. 2)its derivative also continous. 3)It can be normalized, as it tends to...

Hey! I have some dumb-smart question Does 1D line have physical width? My logic says that mathematically you can go smaller and smaller,but I see there being a problem with 1D having infinitly small width in physics. If 2D object has infinitly many 1D lines that would suggest that 2D...

Homework Statement meter stick pivoted at point a from its center and swings as a physical pendulum. At which values of a gives you the shortest period of oscillation...1m, .2m, .3m, .4m. .5m Homework Equations T = 2pi*Sqrt(I/mgh) The Attempt at a Solution the shortest a should...

Can anyone tell me the physical law which is behind certain physical effects? 1. Resonance 2. Adhesion 3. Heat strain 4. Lever effect 5. Surface tension 6. Cutting/Bending 7. Evaporation 8. sublimation 9. Weissenburg effect 10. Torsion It would be really helpful for my research...

So I know what they are and I've been given some really vague and weak interpretations, but I want to build up my intuition and know more about the specifics of curl and divergence. To my understanding now I know that curl is similar to a paddle wheel spinning in a direction dependent on the...

1.the Schrodinger’s cat on test 2.wave - particle two-phase nature 3.entangled state 4.God does not play dice 5.the Bell inequality Please advice about the above statement should be how to write correctly?

Hi. I did well in calc 1, but I got a C in calc 2. I also took both calc 1 and 2 about five years ago. I feel I didn't do well in Calc 2 because i didn't try, not because I was incapable of understanding, but I honestly have NO IDEA what calc 2 was about. However, Physics 2 (with calculus)...

An old QM exam question asked for consideration of a two-level quantum system, with a Hamiltonian of H = \frac{\hbar \Delta}{2} ( {\lvert {b} \rangle}{\langle {b} \rvert}- {\lvert {a} \rangle}{\langle {a} \rvert})+ i \frac{\hbar \Omega}{2} ( {\lvert {a} \rangle}{\langle {b} \rvert}- {\lvert...

Freidel will be giving a talk in the online seminar ILQGS, about Relative Locality---the subject of this paper: http://arxiv.org/abs/1101.0931 The principle of relative locality Giovanni Amelino-Camelia, Laurent Freidel, Jerzy Kowalski-Glikman, Lee Smolin 12 pages, 3 figures (Submitted on...

Hello everyone, haven't been here in a while. My tutor asked me wether I wouldn't be interested in writing a smal program to illustrate one particular case of 3-body problem. I definitely would be, it's just that I've never written any application displaying anything. Numerical calculations...

I have read that many tea masters insist that when infusing a tea that requires less-than-boiling water, you should first let the water reach a full 100 degrees C and let it cool back down to the target temperature, rather than take it off the burner as it is approaching boiling. I think it was...

I am an undergraduate student who wants a good, easy to understand, book for physical chemistry, specialized on topics like equilibrium, kinetics, etc. Please recommend some good books, which have the concepts explained thoroughly.

I'm playing with the PDE toolbox in Matlab and solving Laplace's equation, ∇2V = 0, for various electrostatic geometries. I say 'playing' because I started in the wrong end (or right end, depending on how you look at it) by simple trial and error until the solutions looked like something...

What is the implication of the fact that quantities like electric charge, color etc are conserved not just globally but in local region of space too? I understand the later is more restrictive but what advantage does it offer?

We are considering a stationary curved spacetime fabric. Temporal separation[Physical]is given by: {T}_{2}{-}{T}_{1}{=}{\int \sqrt {g}_{00}{dt} [Limits of integration extending from t1 to t2which are of course the coordinate times] The above integral is path dependent,in the general...

Does anyone have any experience with the military officer candidate school career path for physical scientists? I would like to put my physics B.S. to use, but I don't think I can get into a graduate program. I also don't want to join just to get shipped into a combat zone. What's it like?

Homework Statement A virtual memory system has a page size of 512 bytes, seven virtual pages, and four physical page frames. The page table is as follows: VPN...PFN 0.....2 1.....0 2.....- 3.....1 4.....3 5.....- 6.....- Note: VPN -> Virtual Page Number, PFN -> Page Frame Number...

My question relates to a specific example, namely the square root of two. If one forms a right isosceles triangle with the hypotenuse equal to 2 (be it metres, centimetres or whatever) then the other two sides must equal the square root of 2. But the square root of 2 is an irrational number. If...

Hello! I`m looking for Lagrangian Systems with Lagrangian function containing higher derivatives in t. I would be really happy if someone can tell some higher order Lagrangians with physical relevance. Thanks, Viktor

1. Homework Statement Ok So here's my question. The physical Pendulum consists of a thin rod of mass m = 100 g and length 80 cm, and a spherical bob of mass M = 500 g and radius R = 25 cm. There a pivot P at the top of the rod. (Sorry, I don't have a picture >.<) a) It asks for the center of...

Homework Statement Ok So here's my question. The physical Pendulum consists of a thin rod of mass m = 100 g and length 80 cm, and a spherical bob of mass M = 500 g and radius R = 25 cm. There a pivot P at the top of the rod. (Sorry, I don't have a picture >.<) a) It asks for the center of...

How do you compare physical pain with psychological pain? Which one is more intense and damaging? I think it's psychological. It's hard for others to comprehend unless they have been through it. But when someone sees blood they can imagine the pain. But when soul is wounded, it internal...

A physics student measures the period of a physical pendulum about one pivot point to be T. Then he finds another pivot point on the opposite side of the center of mass that gives the same period. The two points are separated by a distance L. Can he find the acceleration due to gravity, g...

Completing the Square for finding the general solution for a quadratic equation by using a two dimensional drawing is easy. Since we can not so easily draw a three dimensional figure to help in finding a solution to a cubic equation, has any clever mathematician ever found a three dimensional...

Hi all! I came across 2 questions on my course work, and i don't know what is required here, can some one help please? Q.1 Define the common derived units of the following physical quantities; and express them in terms of the base units: Mass, Length, Time and Electric charge (or Electric...

I have been reading that observations of distant quasars over the past decade have been suggesting that there have been minuscule changes in our physical constants. An estimate was given about 1 part per 100000 every billion years. If such a change is indeed happening, then it is safe to assume...

I want to take either a geology or physical geography class; I don't know which one I would enjoy more. If I take geology, it fulfills a prerequisite for another class I would like to take, Speleology; but the likelihood of me taking this class is unlikely. I have a general idea of the...

What is the difference between the Algebra of Physical Space (APS) and the Spacetime Algebra (STA), and why do we need them both?

Homework Statement http://hyperphysics.phy-astr.gsu.edu/hbase/pendp.html#c2 i'm trying to prove to be Homework Equations Letting d = Lcm now we already know \partial^2\vartheta/\partial t^2 = \alpha = mgdT\vartheta / I I tried integrating the whole equation wrt dt so...