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    Research assistant wages?

    So I have to put together a mock budget for a funding proposal. I am unsure, however, how much I need to pay the research assistants I will have working on the project. I also don't have a good idea of how much a professional with a PhD or master's would be paid to work on a project. I...
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    Undergrad Research

    Hi guys, This summer I am looking to get involved in research at my university. I am eager to go and meet with a professor to see if I can hold a position for him, but I am very intimidated and I sometimes feel like I don't know enough to contribute to a research team. I have been told...
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    Inertia tensor

    Homework Statement A thin rod has mass M and length L. What is the moment of inertia tensor about the center of mass if placed along the x axis. Homework Equations I would write the inertia tensor in component notation, but I don't know how to use Latex. The Attempt at a Solution...
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    Energy in infinite square well

    Homework Statement Find the energy of a particle of mass m in an infinite square well with one end at x=-L/2 and the other at x=L/2. Homework Equations Schrodinger Equation The Attempt at a Solution To save time, I won't type the solving of the differential equation which results...
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    Relative speed of two particles

    Homework Statement One particle is shot in the x direction at speed u and a second is shot in the y direction at speed u as well. Show that the relative speed of one to the other is: u(2-(u/c)^2)^1/2. Homework Equations velocity addition: u = (u' +/- v)/(1 +/- u'*v) Lorentz Trans...
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    Reading spacetime diagrams

    Homework Statement Two rockets are sent off at t=0, one from x=0 and the other at x=4. The rocket leaving from x=0 is moving at .8c and the rocket leaving x=4 is moving at .2c. When the paths of the two rockets meet, they send a light signal to x=0. Read off the coordinates in the S frame...
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    Central force motion

    Homework Statement Sketch the elliptical and hyperbolic orbits two objects make around each other if their masses are equal. Next to each, sketch the equivalent one-body orbit. Homework Equations The Attempt at a Solution For the elliptical orbit, I just drew two ellipses that...
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    Differentiating a constraint equation

    Homework Statement z = cr^2 Homework Equations The Attempt at a Solution I have a pretty simple question. What is the second derivative of the z equation. I know that z' = 2crr'. Am I correct to say that z'' = 2cr'^2 or is it something else? Hopefully my question...
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    Finding the force of constraint

    Homework Statement A simple pendulum has a mass M attached at the end of a massless rod of length L. Find the force of constraint the rod exerts on the bob. Homework Equations The Attempt at a Solution It seems easy enough that the mass is constrained by the tension the rod...
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    Motion of a star in a galaxy

    Homework Statement A star is moving in a circular orbit of radius r within a galaxy. What is it's orbital speed v(r) as a function of \rho(r) and radius. The galaxy is spherically symmetric with a mean density \rho(r) and radius R. Homework Equations F =...
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    Complex to polar form

    Homework Statement Show that the solution x(t) = Ge^(iwt), where G is in general complex, can be written in the form x(t) = Dcos(wt - \delta). D(w) and \delta(w) are real functions of w. Homework Equations z = Ae^(i\phi) The Attempt at a Solution So I know I should start by...
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    Driven oscillator with damping

    Homework Statement The oscillator is driven by a force F(t) = mAcos(wt). Plot the amplitude D of oscillations, in units of the maximum (resonant) amplitude D(max), as a function of w in units of w_0. (In other words, plot D/D(max) versus w/w_0.) Find Q. \beta=(1/6)w_0 Homework...
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    Complex roots

    Homework Statement Z^5 = -1 What are the five roots? Homework Equations The Attempt at a Solution I do not know how to start this problem. I am given a hint to put -1 into the form Ae^(i*delta), but I am unsure as to how I can do that. Any help would be much appreciated.
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    Complex notation

    Homework Statement If x= Acos(\omegat + \delta), then one can also write it as x = Re(Be^{i\Phi}). Find B and \Phi in terms of A, \omega, and \delta if B is real. Homework Equations The Attempt at a Solution Not sure where to start on this one. I know you guys can't give...
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    Is this a vector operation

    Homework Statement Consider a new vector operation, 'star' (*), defined for two dimensional vectors by A*B=(A1-B1,A2+B2). Is the resultant object a vector? Homework Equations The Attempt at a Solution I want to say that the resultant object would be a vector but I do not know...
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    Energy conservation and circular motion

    Homework Statement A ball with a mass m swings from a string of length L from a pivot. A distance D directly below the pivot there is a nail. The ball is released making an angle theta=pi/2 with the vertical. For this particular problem, there is no friction. Assuming the ball swings...
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    Transformation Matrices

    Homework Statement Find the components of A after a rotation of -45 degrees about X3. A=(1,1,2) Homework Equations \lambda= (cos\theta 0 -sin\theta) ( 0 1...
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    Bowling ball velocity problem

    Homework Statement A bowling ball is initially bowled so that it doesn't roll with a translational velocity Vo. Show that when the velocity of the ball drops to (5/7)Vo, the ball will begin to roll without sliding. I= (2/5)MR^2 mass= M radius= R Homework Equations V=wR The...
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    Thermo final study tips

    Hey guys, I have my final exam in a week for my thermodynamics class. So far this year, things have been sort of roller-coaster-like. I did poorly on my first test because I was caught completely off guard. On my second test, I raised my grade substantially to the point where I was...
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    Fortran Hangman in fortran

    Hello all, I am attempting to make a fortran program that allows the user to play a game of hangman. So far I have written a complete program that assembles piece by piece the base, gallows, rope, body parts, etc.. I have another completely separate program that reads from a file 264 random...
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    Ideal gas compression

    Homework Statement A compressed cylinder holds nitrogen gas at room temperature. How cold is the gas that is escaping from the cylinder? T(cylinder) = 298 K P(cylinder) = 1.034e7 Pa n = 1 Homework Equations PV = nRT The Attempt at a Solution So since I was not given either the volume of...
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    Physics Careers w/ physics

    Hello all, I am currently pursuing a B.S. degree in physics. My main concern is finding a job that isn't just laboratory research. Can anyone give some of the popular areas that physics degrees would be applicable for? Any advice would be much appreciated.
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    Adiabatic expansion

    Homework Statement Show that when an ideal gas expands adiabatically, the temperature and pressure are related by the differential equation: dT/dP = (2/f+2)(T/P). Homework Equations PV=NkT VT^(f/2) = constant V^(gamma)*P = constant The Attempt at a Solution I started off with the formula...
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    Finding randomization algorithm

    Hello all, I am currently attempting to take a set of data I have acquired and trace it back to the initial algorithm that produced it. My problem is my math level is only at the level of differential equations and I do not have any knowledge in advanced statistical analysis. Anyone have...
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    Proton decay

    Homework Statement Grand unification theories predict that the proton has a long but finite lifetime. Current experiments based on detecting the decay of protons in water infer that this lifetime is at least 10^32 years. Assume 10^32 years is, in fact, the mean lifetime of the proton...
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    Titrations and pka's

    Homework Statement Weak acid analyte with strong base titrant. What is the pKa of the analyte in this titration to the nearest 0.5? Given: titrant molarity is .2250 M ; 50 mL of analyte present ; 20 mL of titrant ; initial pH of 3.0 Homework Equations M1*V1=M2*V2 The Attempt at a...
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    Calculate the pH of 20.00 mL of 0.20 M KHP

    Homework Statement Calculate the pH of 20.00 mL of 0.20 M KHP. Given: pKa1(H2P)= 2.950 pKa2(H2P)= 5.408 Homework Equations k = [H][P]/[HP] The Attempt at a Solution I used this equation and got: 3.91e-6 = [x][x]/[.2] x^2 = 7.82e-7 x = 8.8e-4 = [H] pH = 3.05...
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    Buffer solutions

    Homework Statement If you began with 8.5 mL of 0.35 M NaHCO3, how many mL of 0.10 M HCl would you need to add to get a pH 7 buffer? Homework Equations pH = pKa + log([base]/[acid]) or pH = pKa + log(mmol base/mmol acid) The Attempt at a Solution I have tried making a reaction table, but I...
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    Mean free path calculation

    Homework Statement The resistivities and Fermi speeds of Na, Au, and Sn at T = 273 K are 4.2 µ\Omega·cm, 2.04 µ\Omega·cm, and 10.6 µ\Omega·cm, and 1.07e6 m/s, 1.39e6 m/s, and 1.89e6 m/s respectively. Use these values to find the mean free paths λ for the conduction electrons in these elements...
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    Mixtures of acids and bases

    Homework Statement You prepared a reaction table for 10.0 mL of 0.1 M NH4Cl with 5.0 mL of 0.1 M NaOH. Please choose all of the following that describe the solution that was produced. The choices are: 1. a solution containing only a strong base 2. a solution containing a weak acid and a...
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