Coefficient Definition and 1000 Threads

Flow coefficient in valves doesn't have any units. why?

Hey all, I was recently searching for kinetic friction coefficients, and I noticed that for a reason which is unknown to me, some materials had not been appointed such coefficient. The specific kinetic friction coefficient that I'm looking for is aluminum on greasy/lubricated cast iron. Any type...

I am trying to find out where to get the Thermal coefficient of expansion for glycerin. The only thing I keep getting when using Google is mathematical examples that use glycerin as an example and its coefficient but I need to know where this number is coming from. Ex: 4.85 × 10^-4 (°C)-1

I need to conduct an experiment and measure how what is the coefficient and force of friction of the rubber that pushes down along the edge inside the syringe. The thing is I can’t use a dynamometer.

Hi! Sorry if this isn't a good question, but for an experiment, I wanted to try measuring the coefficient of friction of frozen solutions, but wasn't sure how to do it? I thought that since ice would have a low coefficient of friction, it would be interesting to see if solutions with water and...

Homework Statement: The Task is to calculate the Transmission coefficient with the WKB Approximation of following potential: V(x) = V_0(1-(x/a)²) |x|<a ; V(x) = 0 otherwise Homework Equations: ln|T|² = -2 ∫ p(x) dx I have inserted the potential in the equation for p(x) and recieved p(x) =...

Summary: Hello, I have a task to calculate the air drag coeficient experimentally. I have a cone which I had dropped from height of 1.5 m and measured the time. Then I derived the equation of of velocity and acceleration but they are very complicated. Is there any simpler method? a=g-k/m*V^2

Hello, I have a question with regard to equipment design. How do I calculate the overall heat transfer coefficient for a large pipe who has smaller pipes in it? Say I have water flowing on the large pipe, and inside it there are three pipes with hot acid in them. Assuming they flow concurrently...

GR (bold = mathematical convention) m = 3.2kg |applied force| = + 22.8 N |acceleration| = + 3.02 m/s^2 FBD-hypothetical ^ normal force | friction force <-----*-----------> applied force |...

I tried using coefficient of friction = friction / Normal force, but needed a value for friction. I then tried to find the friction using a = f/m, but was unsure of which value to plug in for force. Simply finding the force given a and m will not yield the correct answer; the net force must be a...

Image1, the exercise. My solution: Image2, my solution The answer is .37 but I keep getting .45 What am I doing wrong?

i tryed putting all the number into that equation but it does not work, i have no clue if i need to include the angle to solve this or not and if i do i have no clue how i would

Are there any instances where kinetic coefficient of friction greater than static coefficient of friction? Is this possible in nature?

Hi there, I have modeled with MAXSURF a few variations of a prehistoric logboat in order to test a few theories. Now, I am trying to look at resistance-performance over a range of speed. To do so, I need to include a constant drag coefficient without knowing the drag force and velocity (both...

I am totally confused about whether it even makes sense to speak of n and p-types materials, when referring to whether the majority of charge carriers are electrons or holes. We can read all over the place that the Hall effect can tell us whether a material is p or n-type, just by checking the...

Could you please explain the term 'co-efficient of static friction'? why do the banking of roads or tracks depend of co-efficient of static friction?and not on the co-efficient of kinetic friction?

I don't really know how to begin this problem. I need some advice

The Hamiltonian of the system I'm working on is in the form : ##\hat H=\dfrac{p^2}{2m}-\dfrac{\partial_z^2}{2m}+V(z)+\gamma V'(z)(\hat z \times \vec{\mathbf p})\cdot \vec{\sigma}## There is translational symmetry in the x-y plane. ##\vec{\mathbf{p}}## is the two dimensional momentum in the x,y...

Dear all, For an assignment, I am trying to find the relationship between the Sherwood number and the Reynolds number in a channel for different laminar velocity profiles, where there is a concentration of a species at both the top and bottom wall which is transported to the fluid. For this, I...

##coefficient\; of \;restitution = \large\frac{Relative\; speed \;after \;collision}{Relative\; speed\; before\; collision} \normalsize= 0##

hello i want to plot the drag coefficient vs x-coordinate using fluent 6.3.26 best regard

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Fg = mg = 50 * 10 = 500 N Fn = mg-ma = 500 - (50.0)(1.0) = 500-50 = 450 I don't necessarily know if this is right and I can't seem to find the Ff or coefficient of friction either. Please Help!

Since the integrand is spherically symmetric I use spherical coordinates \int d\vec{r} = \Omega_d\int_{0}^{\infty}dr r^{d-1} where \Omega_d is the solid angle i d dimensions. Since I am to plot as a function of 1/\beta U_0 (= k_bT/U_0) , I introduce a new varible \Theta = 1/\beta U_0...

Basically, the way I did this problem was to use a table with a known ##n## and ##k##. In this case, I fixed ##n=5##, and ##k=3##. I wanted to find the number of terms with three ##x##'s and two ##y##'s. I labeled each ##x_i##, ##1\leq i \leq 5##; the ##y_i## are labeled the same way. Anyway...

Homework Statement Hello. I have slope = 45 degrees, at distance 36.4cm (0.364m) object gains 2m/s speed. Need to calculate friction coefficient. Correct answer is ( 0,2). How to calculate? Homework Equations 1) t = s/v "t" - time; "s" - distance "v" - speed 2) S =...

Homework Statement Hello, I have a problem with my data analysis from my lab. My goal is to find drift velocity of the electron and it's diffusion coefficient. The experiment looked like this: I've measured the time difference between signals on two gaseous detectors. The source of the signal...

Hi, I was recently tasked to build a mini-sumo robot (10x10cm. 500g. the objective is to push your opponent out of a 75cm. diameter arena or dohyo), and I was wondering about the tires that I'm going to use. I want to increase the friction coefficient as much as I can, so I was wondering how to...

Homework Statement The static friction coefficient on an inclined plane is equal to tan(θ). The problem requires me to prove this also works by using an x-axis parallel to the ground rather than parallel to the incline. I understand how to get tan(θ) using the incline as the x-axis, but I don't...

Homework Statement At a construction side, a small crane is raising two boxes of nails on a plank to the roof. One box has already been opened and is half full, while the other box is new. The boxes, including the nails, weight 10 kg and 20 kg, respectively, and are the same size. Diagram...

Homework Statement ##b_2## is the second virial coefficient Homework Equations Virial expansion: $$P = nkT(1 + b_2 (T)n + b_3 (T)n^2...)$$ $$b_2 = -\frac{1}{2} \int dr f(r) $$ r is the distance vector. $$f(r) = e^{-\beta \phi(r)} - 1$$ The Attempt at a Solution $$b_2(T) = 2 \pi r^2...

What is the coefficient of drag on a flat surface? Note: The body is in free fall The object has 2 wings planform (it's a paper helicopter), which is flat The object's wing spin in a circular motion (anti-clockwise) during free fall

Homework Statement Prove that the Clebsch-Grodan coefficients (in the notation ##\langle j_1j_2m_1m_2|j_1j_2jm\rangle##) for the decomposition of the tensor product of spin ##l## and spin ##1/2## to spin ##l+1/2## are $$\left\langle l,\frac{1}{2},m\mp \frac{1}{2}, \pm \frac{1}{2} \Bigg\vert l...

Why is the void coefficient in enriched US reactors negative?

I am learning binomial theorem now on my long journey to calculus. I noticed that in older textbooks, the binomial coefficient looks like C(n on top,k on bottom) I don’t think that I can display it here and in newer ones,they look like ##\binom{n}{k}## is the old notation outdated?or this is...

Homework Statement I have the following circuit: The two inductors are connected in series are characterized by internal resistances R1 and R2 and self-inductances L11 and L22. The magnetic coupling factor between the inductors is k = 0.75. The inductors carry the same current i. What is the...

I have been attempting to calculate a Ballistic Coefficient (BC) from two velocities of a known distance using the formula: BC = (AirDensity * Distance) / ( SQRT(Velocity0) - SQRT(Velocity1)) for example AirDensity = 0.0751265 lb/ft³ Distance = 100 yards Velocity0 = 3000 fps Velocity1 = 2772...

Homework Statement : A sled starts from rest at the top of a snow-covered incline that makes a 20° angle with the horizontal. After sliding 68 m down the slope, its speed is 17 m/s. Use the work–energy theorem to calculate the coefficient of kinetic friction between the runners of the sled and...

Homework Statement I need to find the explicit formula for the following recursive sequence: ##v_n=\frac{2}{1+q^n}v_{n-1}## where ##0<q<1## is a constant Homework Equations I found the following method to solve it...

I learned that there are two different definitions for the coefficient of restitution: e = final relative velocity / initial relative velocity and e = √(final KE/initial KE). However, I don't understand how these two definitions will always give the same value. If one particle with mass m...

Homework Statement So in physics we have this lab. Its simple, I'm just bad at physics...so bare with me. The objective of the lab is find the coefficient of friction (on a flat surface not on inclined planes and such not sure if this makes a difference (I should know if it does but I don't and...

Why is the absorption coefficient (##\alpha##) of water is always given using the units ##\text{length}^{-1}##, while for other materials it is often given by ##\text{length}^{2}.\text{mass}^{-1}##? For instance, this paper uses ##cm^{-1}## for water and yet ##cm^2 / \mu g## for other...

Homework Statement A man pushes a 50 kg box up a 20-degree ramp at constant velocity. If the pushing force is parallel to the ramp, and the coefficient of friction is 0.4, how much force is he pushing with? Homework Equations u=Fs, max/Fn Not sure if this equation is needed. The Attempt at a...

Homework Statement Homework Equations [/B][/B] 3. The Attempt at a Solution Here's my solution attempt: NOTE: Evolution 2 to 3 is really an isothermic process, but in the diagram shows as an politropic process. 4. Further Questions But it isn't giving me logical values of COP...

Consider this Ito proces: $$dX_t = \mu(X_t,t)dt+\sigma(X_t,t)dW_t$$ with W_t being a wiener process. My question: What is the diffusion coefficient of X? My motivation for asking: A lot if financial literature refer to "diffusion coefficient" and I haven't understood by googling it, because...

Homework Statement In a particular fibre, the attenuation coefficient for Rayleigh scattering is measured to be 0.30 dB/km at 1.20 μm. (a) How large would it be expected to be at 0.80 μm? (b) Ignoring other sources of attenuation, if a signal of a certain initial power was sent over a...

I was wondering that if rolling resistance is basically caused by slight deformation of a body, we must have formulas in place to relate it to the physical and material properties of a body. But when I went ravaging for it in library or internet, everything was experimental. I wished to know...

Homework Statement Coefficient of xy(z^-2) in (x-2y+3(z^-1))^4 Homework EquationsThe Attempt at a Solution [/B] I was wondering if anyone could give me an explanation for my answer? The coeffecient of xy(z^-2) does not = 4 where I would be able to use the multinomial theorem. So since I...

Hi all, I have a suspended seat with a scissor mechanism like the following: This seat is composed of coil spring and a hydraulic damper. My aim is to develop a multibody model of that seat. Actually, my model is quite complete, only the parameters of damper are missing (i.e. the damping...

I have conducted an experiment that measures the velocity of an object that is moving on a flat surface. The object rolls on four fixed caster wheels. The wheels are made of some kind of rigid material. Maybe nylon, maybe hard rubber. The total mass of the object, including the wheels, is...