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    Kondo Lattice vs. Single Impurity Kondo System

    In order for a dilute magnetic alloy to show the kondo effect (resistance minimum at low T), the magnetic impurites must be far apart and non-interacting. In the Kondo lattice, the magnetic impurities are much closer togeather (one impurity per unit cell), so why does this system show the...
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    Falling bodies

    If two objects of equal mass are dropped....one from h1 and the other fro h2.....will they hit the ground with the same force? Because the only force acting on the objects is gravity so we can say: F=ma and the acceleration is constant...so the forces must be the same. Is this...
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    Au doped with Fe Spin Glass

    Hello everyone, I am an undergratude student doing to research and I am making dirty Au films. At certian concentrations of Fe (say >.5%) this Au-Fe is showing charateristics of a sping glass. I am attempting to learn what exactly a spin glass is and what its trends look like (resistance vs...
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    C/++/# Sovling schrodinger's equation in C++

    i need help coming up with a way to solve for the eigen vectors of schrodinger's time independant equation in c++. so i want to write a class that uses the shooting method, but i am not sure how to do that.
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    Determine the electric flux through each of the sides

    A 2.10- mC charge is placed at the center of a cube of sides 6.40 cm. Determine the electric flux through each of the sides. ok so electric flux=E(A) so i figure that the electic flux will be the same for all six sides of the cube so i am just calculating the flux on one side then X6...
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    Partial fraction decompostion

    (2x+3)/(x+1)^2 so this is what i am thinking...but it does not make sense =(A/x+1)+(B/(x+1)^2) so then 2x+3=A(x+1)^2+B(x+1) 2x+3=Ax^2+A2x+A+Bx+1 so that would make... 0=A 2=2A+B 3=A+B this solution does not make any sense becuase if A=0 then according to the second...
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    Charges on the vertex of a triangle

    Positive point-charges of +16.0 mC are fixed at two of the vertices of an equilateral triangle with sides of 1.30 m, located in vacuum. Determine the magnitude of the E-field at the third vertex. so...all the particals are in equalibrum so that means F=ma=0 so if i call the third vertex...
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    Electric field and ball of charge

    As shown in the figure above, a ball with a mass of 0.180 g and positive charge of q=31.0 mC is suspended on a string of negligible mass in a uniform electric field. We observe that the ball hangs at an angle of q=16.0o from the vertical. What is the magnitude of the electric field...
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    Some-what fancy trig inegral

    find the integral of (cosx)^2(tanx)^3 so first of all i rewrote tan to be (sinx)^3/(cosx)^3 so that i could cancle out the (cosx)^2 on top and now i have the integral of (1/cosx)(sinx)^3 i rewrote that to be (tanx)(sinx)^2...and now i am stuck i don't know of any IDs that could...
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    Electric charge and total force

    Three charges, Q1, Q2, and Q3 are located in a straight line. The position of Q2 is 0.279 m to the right of Q1. Q3 is located 0.180 m to the right of Q2. In the above problem, Q1 = 1.90 × 10-6 C, Q2 = -2.65 × 10-6 C, and Q3 = 3.18 × 10-6 C. Calculate the total force on Q2. Use a plus sign for a...
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    Integration by parts

    intergrate (ln(x))^2 so i set u=(lnx)^2...which makes du=2lnx(1/x) then i set dv=dx...which makes v=x according to the formula for integration by parts i have x(lnx)^2- integral x(2lnx)(1/x) simplifying it i get x(ln)^2-2intergral lnx and here is where i am stuck....what i the...
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    Angular momentun

    a 2-kg partical moves at a constant speed of 4.5 m/s along a stright line. what is the magnitude of its angular momentum about a point 6 m from the line? ok...so i really don't know what they mean by 'the partical is travling in a stright line about a point 6m away from the line' doesn't...
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    Adiabatic compression of an ideal gas

    An ideal gas at a temperature of 17.7°C is compressed adiabatically from an initial volume 70.0 l to a final volume 43.0 l. Find its final temperature (in °C) if CV = 2.50R. so T1V1^g=T2V2^g to find g=cp/cv=(cv+nR)/cv and cv=2.50R g=(2.50R+nR)/2.50R factor out an R...
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    Find the work done by the gas

    55 moles of an ideal gas, at an initial pressure of 3.00 × 105 N/m2 and an initial volume of 1.700 m3, undergo a small isothermal expansion to a volume of 1.720 m3. Find the work done by the gas. i am confused about the units but here is what i got... so w=nRTln(vi/vf) so i know n...
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    Pressure and scuba

    A scuba diver at a depth of 43.0 m below the surface of the sea off the shores of Panama City, where the temperature is 4.0°C, releases an air bubble with volume 17.0 cm3. The bubble rises to the surface where the temperature is 19.0°C. What is the volume of the bubble immediately before it...
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    Annoying pressure prob. that is so easy i should not have to ask for help

    A child's helium-filled balloon escapes at sea level and 20.0°C. When it reaches an altitude of 2530 m where the temperature is 5.60°C and the pressure only 0.710 atm, what is the ratio its volume compare to that at sea level? so i am going to use the ideal gas law... that is...
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    Doppler effect sensitive parabolic sound collector

    Using a highly sensitive parabolic sound collector, Tom records the frequency of a tuning fork as it drops into the Grand Canyon. He drops the vibrating tuning fork from rest at t=0. He records a frequency of 1887.0 Hz at t=7.880 s. What is the natural frequency of the tuning fork? Use...
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    Simple harmonic frequency clarification

    A massless spring with spring constant 23.5 N/m hangs vertically. A body of mass 0.30 kg is attached to its free end and then released. Assume that the spring was unstretched before the body was released. What is the frequency of oscillation of the resulting motion, assumed to be simple...
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    Gravational field 2

    Two isolated masses, M1 = 2.20 kg and M2 = 607 kg are initially rest, a distance d = 171 cm apart. Their gravitational attraction is the only force acting. Calculate the time it takes for M1 to move from that distance to 169 cm from M2. Assume that M2 does not move and that the force is constant...
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    Gravational field

    Some believe that the positions of the planets at the time of birth influence the newborn. Others deride this and say that the gravitational force exerted on a baby by the obstetrician is greater than that exerted by the planets. To check this claim, first calculate the gravitational force...
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    Simple antiderivative

    Find f if f '(t)=8cost+sec^2t and f(pi/3)=4 . so f(t)=8sint+tant+c 4=8sin(pi/3)+tan(pi/3)+c c=-3^1/2 so f(t)=8sint+tant-3^1/2 is that right
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    Static equilibrium and torque calculation

    Misako is about to do a push-up. Her center of gravity lies directly above a point on the floor which is d1 = 0.96 m from her feet and d2 = 0.71 m from her hands. If her mass is 50.0 kg, what is the force exerted by the floor on her hands? F(feet)+F(head)=F(center of gravity0) becuase she is...
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    Force of the track on a rollercoaster

    a roller coster car of mass 1500 kg starts at a distance of H=23m above the bottom of the loop 15 m in diameter. if friction is negligible, what is the downward force of the rails on the can when it is upside down at the top of the loop? so what i was thinking is this: f=ma and in this...
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    Projectile motion rock throw speed

    a rock is thrown from the tope pf a 20m buliding at an angle of 53 deg. above the horizontal. of the horizontal range of the throw is equal to the hieght of the buliding, with what speed was the rock thrown? if i am given range i am trying to use x=xo+vot+.5at^2 but i don't know the time...
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    Two stones off a cliff

    2 stones are dropped off a 60 m cliff the second stone is droped 1.6 s after the first one. how far below the top of the cliff is the second stone when th seperation between the 2 stones is 36 m? so i am trying to use the equation x1=xo+tvo+.5at^2 then x2=xo+(t+1.6)vo+.5a(t+1.6)^2 or...
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    Mean value theorem

    Verify that the function satisfies the hypotheses of the Mean Value Theorem on the given interval. Then find all numbers that satisfy the conclusion of the Mean Value Theorem. f(x)=3x^2+6x+7 on [-2,3] so f(3)-f(-2)=f'(x)(3+2) i get 52-7=(6x+6)(5) then 45=30x+30 then 5=30x...
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    Bat and ball collison

    A ball and bat, approaching one another each with the same speed of 1.7 m/s, collide. Find the speed of the ball after the collision. (Assume the mass of the bat is very much larger than the mass of the ball, a perfectly elastic collision, and no rotational motion). so i am going to use...
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    Collison betwen two balls

    Two identical steel balls, each of mass 1.4 kg, are suspended from strings of length 36 cm so that they touch when in their equilibrium position. We pull one of the balls back until its string makes an angle q = 36° with the vertical and let it go. It collides elastically with the other ball...
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    The unit of momentum

    what is the unit of momentum? i know that p=mv which has units of kg*m/s but is there another way to write it?
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    Find the linearization

    Find the linearization of f(x)= x^1/3 at a=-64 so i am trying to use f(x)=f(a)+f'(a)(x-a) f(a)=-4 f'(x)=1/3(x^-2/3) f'(a)=-1/48 so i get -4+1/48(x+64) is that right?
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