Coefficient Definition and 1000 Threads

A crate is in a pickup truck traveling horizontally at 15.0 m/s. The trucks apply the brakes for 28.7 m while stopping with uniform acceleration. What is the coefficient of static friction between the crate and the truck bed if the crate does not slide? I know how to solve for the...

How can I understand "reflection coefficient" for a certain circuit? Homework Statement I'm a beginner in RF circuit, though I've learned something about low frequency oscillator design, some new concepts still confuse me a lot, like the "reflection coefficient". I google it and found...

I have done a lab experiment, to determine the coefficient of lift for an aerofoil, keeping the angle of attack constant. The equation I have used is Lift= (1/2) v times v times A times ρ times Coefficient of lLift v= Velocity of air ρ=air density A= planform area to give...

The Klein Paradox is the name given to the following prediction of Klein Gordon's equations. If you send a current of electrons against a potential barrier of height V such that the energy of the incident electrons is less then V - m, you should observe a current of positrons coming out of the...

I'm doing a lab for my technical dynamics class and that lab is to determine the coefficient of static friction between a metal washer and both metal and rubber surfaces. I did the experiment using 3 washers set at different distances from the center of the turntable as instructed, and...

Homework Statement A 100g mass moves on the end of a spring with force constant . It is released with an amplitude 0.2m. A damping force acts on the egg. After it oscillates for 5.00 s, the amplitude of the motion has decreased by 0.1m.Calculate the magnitude of the damping coefficient ...

Homework Statement One liter of water at 30 C (30000 calories ) A 100 gram sphere of ice at 0 C in center of water volume . The ice will absorb 80000 calories melting, and final water temperature = 22000 cal/1100g = 20 C. Assume mixing and uniform water temp during melting and water vessel...

Homework Statement A force of 40.0N accelerates a 5.0-kg block at 6.0M/s^2 along a horizontal surface. a. What is the frictional force? b. What is the coefficient of friction? Homework Equations u= coefficient of friction m= mass of object Ff= friction force g= gravity u=Ff/mg...

A 1.0 kg copper rod rests on two horizontal rails 1.0 m apart and carries a current of 50 A from one rail to the other. The coefficient of static friction between rod and rails is 0.60. What are the (a) Magnitude and (b) Angle (relative to the vertical) of the smallest magnetic field that puts...

Homework Statement One liter of water at 30 C ( 30000 calories ) 100 gram (100 cc ) sphere of ice at 0 C is in center of water volume. The ice will absorb 8000 cal melting and final water temp = 22000 cal/ 1100 g = 20 C Assuming mixing and uniform water temp during melting ,and vessel is...

What is the acceleration of a 25kg block sliding down a ramp at 30 degrees to the horizontal, if the coefficient of friction is 0.3? ans= 2.4m/s2 I haven't done this in a while.. I can't remember how to apply the coefficient of friction.. Thank you! [SIZE="4"]PLEASE DISREGARD...

Homework Statement I have this equation: T=(1+\frac{U_{0}^{2}}{4E(U_{0}-E)}sinh^{2}(2 \alpha L))^{-1} Where α is given by: \alpha = \sqrt{ \frac{2m(U_{0}-E)}{\hbar^{2}}} I have to show that in the limit αL>>1 my equation is approximately given by...

Homework Statement A car is traveling at 30m/s around a bend of radius 70m. What coefficient of static friction between the tires and the road is required to ensure the car will not slip? Homework Equations The Attempt at a Solution I know that the centripetal acceleration is...

Consider a proposed airplane design shape in a wind tunnel. The forces and moments are measured at the proposed center of gravity location. At zero angle of attack, pitching moment is zero and lift is 10N. At 5 degrees angle of attack, pitching moment is -5Nm and lift is 60N. The chord of the...

Hi everyone, I'm completely new to the aero engineering and have a question regarding drag. The lecturer explained it briefly, threw some formulae at us and now I'm confused trying to make sense of it all. So, i have these two formulae relating to drag: 1) D = 0.5(rho)(V^2)(A)(Cd) and...

Homework Statement A 5.0 kg mass is held against a wall with which it has a coefficient of static friction of 0.85. What is the minimum horizontal force required to hold the mass against the wall ? The teacher said answer is 58 N .. i can't get to that answer.. Homework Equations...

An electron having total energy E=4.46 eV approaches a rectangular energy barrier with U=5.02 eV and L=949 pm. Calculate this probability, which is the transmission coefficient. I thought this would be an easy one, given that T=e-2GL and G=\sqrt{\frac{2m(U-E)}{H}} where H is the...

Homework Statement We have a block of wood that has a weight of 95.5g lying on another flat piece of wood. The block of wood has a string attached to a tray that hangs over a pulley. Wehad to add weight to the block adn then to the tray to see how much weight in the tray would break the...

I have been trying to solve a differential equation that will be used to determine voltage and current variations based on ambient temperature and the distance along the line. To avoid the complicated derrivation of the current equation... the current based off the temperature variations should...

Hello I am kinda confused when it comes to finding a general solution of equation. Here is the question. Y'' + 6Y' +9Y = 0 Solution Y'' + 6Y' +9Y = 0 I used "x" instead of Lamda...ANYWAY X^2 + 6X + 9 = 0 FACTOR IT WHICH IS (X+3) (X+3) = 0 X IS EQUAL TO -3. HERE IS WHERE I...

Homework Statement A block of wood is sitting on an inclined plane. One end of the plane is rised until the wood block slides down. The wood block slides down when the plane has an angle of 17.157 degrees . What is the coefficient of friction? Homework Equations F/R The Attempt...

Hi there :) At 19\circC, a rod is exactly 20.08 cm long on a steel ruler. Both the rod and the ruler are placed in an oven at 285\circC, where the rod now measures 20.18 cm on the same ruler. What is the coefficient of linear expansion for the material of which the rod is made? I used the...

Homework Statement A child goes down a playground slide with an acceleration of 1.32 {m/s^2}. Find the coefficient of kinetic friction between the child and the slide if the slide is inclined at an angle of 35.0 deg below the horizontal. Homework Equations Fnet=ma Fg=mg Ff=uFn I...

Homework Statement A 82.0 cm pendulum is released from a small angle. After 112 oscillations the amplitude is one half of its original value. The damping is proportional to the speed of the pendulum bob. Find the value of the damping coefficient, α, (in Hz). Homework Equations x =...

Homework Statement A book has a mass of 400 g. When you slided the book against the floor with 5 N, it accelerated at the rate of -1.5 m/s2. What would the coefficient of friction between the book and the floor be? Homework Equations F = ma W = mg FN = - mg The Attempt at a...

Coefficient of friction--Puck traveling up an incline Homework Statement A hockey puck is moving at 13m/s when it starts climbing an incline. It travels 7.1m from the base of the incline before sliding back down the slope, as shown Find the coefficient of friction between the puck and the...

Here is my problem. A rod spinning about it's cg of angular speed omega. So there is no linear momentum, I believe that's correct. Just angular momentum. A ball, v_i = 0, impact the rod at radius, r. The coefficient of restitution is e. How do I use this to find the final velocity of...

1. You have a heat pump which has a coefficient of performance (C.O.P.) that is 17% of the maximum achievable. You want to heat your house to 20◦C. At what outside temperature does the heat pump become not useful? 2. C.O.P. = 1/(T1/T0 - 1) T1= Temperature of the outside...

Homework Statement Find the coefficient of x^36 in (x^2 + x^3 + x^4 + x^5 + x^6 + x^7 + x^8)^6 Homework Equations 1/(1-x) = 1 + x + x^2 +... (where +... indicates an infinite series). (1 - x^(m+1)/(1-x)) = 1+x+x^2+...+x^m (I'll call this identity 'TWEAK') The Attempt at a...

Homework Statement Find the transmission coefficient for the potential V(x)=-\alpha\left[\delta\left(x+a\right)+\delta\left(x-a\right)\right], where alpha and a are positive constants. Homework Equations T \equiv \frac{\left|F\right|^{2}}{\left|A\right|^{2}} The Attempt at a Solution...

Homework Statement I don't understand why flow coefficient increases with Re and why it becomes independent after a certain Re number for orifice plates and venturi meter! Homework Equations The Attempt at a Solution It seems than when the flow becomes turbulent, the flow...

How to obtain the coefficients of normalized wavefunction for the hybrid orbital in sp2 hybridization (esp in BH3) , which normally in surds? In what way symmetry affect the linear combination of the atomic orbitals ? Will appreciate if anyone could help or provide some beginning guides , thanks...

Homework Statement Solve ODE of form y''+(2/x)y'=C*(e^y) where C is a constant Homework Equations The Attempt at a Solution I don't really see how to approach this one, so a point in the right direction would be great. Thanks,

Dear All, I have a PDE like: A * d2w/dy2 + B * 1/x * d2w/dx2 + C * w = 0 where , w = w(x,y), A & B & C are constants. Is there any analytical solution for this PDE? If not, is finite difference is the right numerical tools to solve it? Thanks, Frank

Homework Statement A mop is being used to clean a floor. The coefficient of friction between the mop and floor is 0.3. Find the angle between the handle and the horizontal when the mop head is moving at constant velocity. Homework Equations The coefficient of friction = Friction/ Normal...

The coefficent of static friction between the floor of a truck and a box resting on it is 0.40. The truck is traveling at 82.9 km/hr. What is the least distance in which the truck can stop and ensure that the box does not slide? No idea where to even start...

Homework Statement A 3 kg block slides down a 30 degree inclined plane with constant acceleration of 0.5 m/s2. The block starts from rest at the top. The length of the incline is 2 m. What is the coefficient of friction between the plane and the block? Homework Equations Ff=uFn...

A 50.0 kg chair initially at rest on a horizontal floor requires a 365 N horizontal force to set it in motion. Once the chair is in motion a 327 N horizontal force keeps it moving at a constant velocity. Find the coefficient of friction between the chair and the floor. (In this problem use the...

Homework Statement I am trying to find the mtuual inductance between two p-core inductors (they share the same core) but I am not sure how the coupling coefficient would be calculated. I know the inductance of both coils. What else would I have to know in order to calculate the coupling...

Homework Statement Jeff Gordon (a race-car driver) discovers that he can accelerate at 4.0m/s2 without spinning his tires, but if he tries to accelerate more rapidly he always "burns rubber." Find the coefficient of friction between his tires and the road. Assume the force from the engine is...

Homework Statement A car is moving with a velocity of 20m/s when the brakes are applied and the wheels lock (stop spinning), The car then slides to a stop in 40m. FInd the coefficient of kinitic friction between the tires and the road. Homework Equations F=ma Ffriction=coefficient...

Consider a 2D variable coefficient linear recurrence relation. An example might be: b_{n,j+1} (j+1)(2n-1)(2n-2) = (2n-2+j)(2n-1+j)b_{n-1,j} which has the solution b_{n,j} = \frac{(2n-1+j)!}{(2n-1)!j!} Is there any algorithm that can be used to derive this result? I have a recurrence...

Homework Statement in a demonstration designed to determine the coefficient of friction for a book on a wooden plank, one end of the plank was raised until the book on it began to slide. if sliding commenced when the plank was at an agle of 37 degrees above the horizontal, what was the...

Does anybody know? I tried googling can't seem to turn up any answers

1. find the complex Fourier series and the real Fourier series f(t) = 0 , -pi <= t < 0, f(t)= t, 0<=t< pi Homework Equations 3. to find the coefficient ck i got 2 different answers one is if the index k is even and another if the index is odd, how am i supposed to represent this...

hello ppl, i have a question about the reflection coefficient... since the RC indicates the permeabilty of a membrane for a specific molecule...doesnt that mean (If the RC between 0 and 1) that the concentration of that molecule on both sides of the membrane will become the same after a while...

Homework Statement Hello! I am supposed to explain the behaviour of the thermal conductivity of tungsten. I have plotted the relation http://img340.imageshack.us/img340/9776/heatcond.jpg is also experimental data Temp[0 10 50 100 300 500 1000 2000 3400] and thermal conductivity...

1. The problem statement A 10 kg block is released from point A on a track ABCD. The track is frictionless except for the portion BC, of length 6 m. The block travels down the track and hits a spring of force constant k = 2250 N/m and compresses it a distance of 0.3 m from its equilibrium...

I know the steel-steel COF is about 0.8. Are the tribological properties of different steels, eg austenitic and 9%Cr, sufficiently different that this difference should be taken into account in the design of a component that will slide over two different steels, or sufficiently similar that the...

why the coefficient of friction of screw jack of two pulley is negative in lowering state?