Coefficient of friction Definition and 416 Threads

Does anyone know where I can get those values? Haven't been able to find them anywhere

Homework Statement A 30kg sled is sliding on a frictionless sheet of ice at a velocity of 4m/s. The sled encounters a rough patch of ice and begins to slow down. After traveling on the rough patch of ice for 3m, the sled's velocity is 2m/s. Determine the coefficient of friction between the...

1. a worker can supply a maximum pull of 150 lb on a cart w/c has a handle set at an angle of 40° above the horizontal. what is the coefficient of friction if he can just move a total load of 1500 lb ? 2. μ = Ff/mg 3. so i solved it by 150sin(40) divide by 1500cos(40), but I'm not...

Homework Statement Two men loading a 900 kg piano onto a truck lose control and the piano slips, rolling down the loading ramp. The ramp is a 12 degree incline that is 3.2m long. If the piano accelerates down the ramp at 0.4m/s^2, find the coefficient of rolling friction. Homework...

Hello Fellow Forum, How would you calculate the coefficient of friction for sandpaper? I'm testing mechanical resistance of a bioplastic, and I'm going to attach the bioplastic to different weights, and then rub sandpaper over the bioplastics. The one that breaks will be used to find...

What is the minimum force needed to overcome static friction on a block whose normal force is 5.2N and has a coefficient of static friction 0.34? A desk is pushed with a constant velocity along a floor. If the mass of the desk is 25kg,and the force required to keep the desk moving is...

A 20 Kg. mass slides up on an infinitely long inclined plane (that forms an angle of 30º with the horizontal) with a velocity of 12 m/s. It's known that the mass returns to the starting point with a velocity of 6 m/s. Find,μ, the coefficient of friction between the plane and the body. This is...

1. A 4.0 m long bar is suppotred by a string as shown in Figure 10-61. What must be the coefficient of friction between the bar and the floor if the bar is on the verge of slipping Image: 2. τ = r*F*sinθ or τ = r*F, where the force is perpendicular to the radius. Summation of...

hello everyone. Can anyone please help with following questions? 1. Can coefficient of friction (both static and dynamic) be greater than one? What happens if it is greater than 1 ? 2. Why coefficient of kinetic friction is less than coefficient of static friction and why it decreases at...

1. Here is the problem http://i.imgur.com/WH0Z4ko.png So I've set up a Free Body Diagram and I think I have it right. I have the two Forces of Weight (8.82N and 21.27N), the force of 12.8 that is pulling the .9kg box, and then the Force Normal (just the opposites of the two Forces of...

Homework Statement You are to lower a safe of mass 260kg at constant speed downs skids 20.0m long, from a truck 2.0m high. a) If the coefficient of friction between the safe and the skids is 0.25, do you need to pull the safe down or hold it back? b)How great a force parallel to the skids is...

A road vehicle equipped with mechanical wheel brake e.g drum or disc brake ,driving at a speed of 100Km/hr is braked to a stand still with a deceleration of 1G (3.2m/sec^2),How large must be the coefficient if friction between wheel and road at least be to enable that. Options: 1)At least...

Homework Statement A man of mass m is applying a horizontal force to slide a box of mass m' on a rough horizontal surface. It is known that the man does not slide. The coefficient of friction between the shoes of the man and the floor is ##\mu## and between the box and the floor is ##\mu'##...

Hi, Will I have a higher slipping force / torque by increasing the width of my brake shoe and drum? Though my instinct says it is possible, textbook says it's only the coefficient of friction that controls the slipping force. Can you pl help me understanding this? Thanks.

Homework Statement a block with a mass of 0.310kg at a constant velocity , calculate the coefficient of kinetic friction on an incline plane Homework Equations f=ma fg=mg fparallel= mg* sin30 degreesThe Attempt at a Solution I found the FN which is 2.60 and the f parallel to be 1.52. i...

Say if an iron disk slides down a non ferromagnetic conductor ramp and we get a certain time. And then we have an iron disk with the same mass but MAGNETIZED slide down the same ramp and get a longer time (because of of magnetic braking). The calculated acceleration of the MAGNETIZED disk will...

Physics coefficient of friction question! A 17kg box is being pushed by a 150N force. If the box is accelerating at 2.3m/s2. What is the coefficient of friction on the ground?FNet=μFn Fn= 9.8x17= 166.6N How can I find the fnet?

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. Homework Equations Vf^2=Vi^2 +2ad velocity is 1.414 Fg=3 x 9.8=29.4 Fn= cos(30) (9.8 x 3) = 25.5...

Hey all, I'm trying to design a clamp that has to hold onto a hollow carbon fiber tube, approximately 2.5 inches in diameter. The clamp will be bearing a 15-20lb load. The carbon fiber will be at angles from 20-70 degrees from a vertical axis. I'm curious if there is a polymer that can be...

Homework Statement You do 2.2 kJ of work pushing a trunk at a constant speed 3.1 m along a ramp inclined upward at 22 degrees. What is the frictional coefficient between the trunk and the ramp? Homework Equations W = F*d Ff = μmg * cos(θ) Fg = mg * sin(θ)The Attempt at a Solution To find the...

Homework Statement A small 15 kg cardboard box is thrown across a level floor. It slides a distance of 7.0 m, stopping in 3.3 s. What is the coefficient of friction between the box and the floor? Homework Equations The Attempt at a Solution I didn't know how to do it. I just...

Homework Statement A wheel has a radius of 0.4m . The engine exerts a torque on the wheel of 290 Nm. FInd the coefficient of friction. Homework Equations T=RFsin T= Angular acceleration * Inertia (1/2MR^2)? The Attempt at a Solution My friend asked me this question, but I feel...

Hello I'm new here and to be quite honest not sure if I'm posting this in the right section, so apologies up front if I have this wrong. Basically I was wondering if anyone has any idea on why the dynamic coefficient of friction for aluminium on aluminum is greater than the static coefficient...

What is the coefficient of friction between a 65-kilogram chair and a floor if the chair can be pushed at constant speed with a force of 220 Newtons? My attempt: Given: m=65 kg Ffr (force of friction)=220 N w=mg=(65)(9.8)=637 Fn=637 N μ=? μ=Ffr/Fn μ=220/637 μ≈0.345 Is this right? I...

Homework Statement a block of mass 2kg is in at rest on a rough plane inclined at 30°, it is in limiting equilibrium with with a force of 20N applied horizontally (to the ground). Find the coefficient of static friction between the block and the plane.The Attempt at a Solution...

Homework Statement Two objects are connected by a light string that passes over a frictionless pulley as shown in the figure below. m1 = 8.32 kg, m2 = 6.40 kg, and = 56°. When released from rest, m1 accelerates downward at 2.210 m/s2. For this to happen, the coefficient of kinetic friction...

A banked circular highway curve is designed for traffic moving at 61 km/h. The radius of the curve is 201 m. Traffic is moving along the highway at 44 km/h on a rainy day. What is the minimum coefficient of friction between tires and road that will allow cars to take the turn without sliding off...

Is there theoretically any way to compute a coefficient of friction (solid on solid) without an experiment between the two materials? Say, some kind of simulation, or perhaps comparing both materials to an intermediary material?

Hi Everyone, I'm trying to find the initial speed of a motorcycle that was involved in an accident. The driver lost control and the bike dragged along the asphalt for some distance. I know several variables but my physics is not a strong suit to say the least. Any help would be much...

Coefficient of friction!? Homework Statement How would you figure out the coefficient of sliding friction between two sheets of paper ?. Homework Equations The Attempt at a Solution I intended to make a ramp out of one paper and and put the other paper on top of the ramp. Adjust...

Homework Statement The coefficient of static friction between two blocks is .60. The coefficient of kinetic friction between the lower block and the floor is .20. If a horizonatal force is applied to the upper block (m=4kg) what is the minimum amount of time the two blocks (m=7kg) can cover...

I shoot a bullet of mass m with velocity v against a block of mass M. Find how far the bullet penetrates the block. This problem turned up in my friends examination and I believe it can't be done without the coefficient of friction. Am I right or can this be calculated using conservation of...

Homework Statement Derivation of an equation for the coefficient of kinetic friction *Since it's just a derivation, values won't be required, right? *No mass was given Homework Equations Ff = μFN FN = FgCosθ Fnet= Fapp - Ff - FgSinθ <- Not sure about this. The Attempt at a...

I have fairly basic questions. How do wheels roll on a surface ? As in what should be the ideal Coefficient of Friction between the wheel surface and the ground, for conditions like "no-slips" What I understand is if there is no friction between the wheels and the ground , the wheels would...

Friction and Relation of Coefficient of Friction to "Smoothness" In my physics class today my teacher began discussing a very peculiar characteristic concerning the static and dynamic coefficients of friction. Apparently, when one makes an object's surface "smoother" (meaning with less...

Homework Statement A crate is placed on an inclined board. The coefficient of friction between the crate and the board is 0.26 , and the angle of the slope is 16 degrees. Calculate the acceleration of the crate down the incline. Homework Equations F=ma Ff=umgcos(theta) Forge of gravity...

Hi, i have a set up where i have a block of wood with sandpaper on the bottom, and a 500g mass on top. Given the grade of the sandpaper, i know the average particle size on the sandpaper. This set up is placed on top of a piece of MDF. Is there a way I could calculate the coefficient of...

I have a part that will slide by it's own weight (50lbs.) at 12 degrees on two parallel shafts. I need to reduce the angle as much as possible. By rotating the shafts, I would reduce the coefficient of friction between the part and the shaft. How would I find the new value of friction due to the...

So I've been busting my head for the past 2 days trying to figure out what I was doing wrong and I just can't. I have a whole bunch of these types of questions and can't solve any of them. My own equations and reasoning make sense to "me" but don't lead me to the right answer. I am positive I'm...

Homework Statement A car is traveling at 15.5m/s travels on a surface where μ=0.1. The driver sees a boy run into the road 125 m ahead. She immedietly applies the brakes, locking the wheel, and skids to a stop. Where will the car be when it stops? (i.e:Will it hit the boy?) I know I should...

Homework Statement From http://library.thinkquest.org/10796/index.html (#6) g=9.80m/s^2 Homework Equations F=ma F_f=\mu F_N F_N=mg (The site actually states the normal force to be equal to negative mass times gravitational acceleration, but with a negative value for gravitational...

Homework Statement Homework Equations I believe: F = m . a Ffriction = μs . N Ffriction = μs . mg . cosθ The Attempt at a Solution I don't quite get how the equations above would give me an answer to the minimum friction required so that the farmer doesn't slip. I know Fl =...

Homework Statement Calculate the coefficient of friction between the wooden block and the table top, using a pendulum to hit the block. Mass of pendulum weight = 1 kg Mass of wooden block (with weight on top) = 2.073 kg Release height of pendulum = .06 m Pendulum's distance from...

Homework Statement A prism has a mass of m = 80 g, and you wish to lift it, touching the upper two faces only. If the coecient of friction between the prism’s surface and your skin is  = 0:4, what is the minimum force that must be applied to each face? Homework Equations F=μR...

I don't understand what determines the coefficient of friction. Can someone explain it to me using examples?

Homework Statement One of the most popular rides at carnivals is the one that resembles a large circular drum that rotates on its axis. Once the ride is spinning fast enough, the floor drops down and the riders are left pinned to the inside wall of the drum (I believe they are describing a...

Hey guys! Ok, so I don't have that much to work with, and I am sorry for my lack of detail, but my memory is a bit fuzzy. I had to do a problem like this for my physics test yesturday: On the test we were given a problem involving a roller coaster (Rotating Drum of Death was its name)...

Here is the problem: "A small package rests on the horizontal dashboard of a car. If μs = 0.333, what is the minimum acceleration of the car that will cause the package to slip off, assuming that the car is on a level road?" I really have no clue. Any equations I feel are relevant (μ...

Homework Statement A block begins to slide down a ramp after being elevated to an angle of 53.75 degrees. What is the coefficient of static friction? Homework Equations The Attempt at a Solution

Homework Statement A block slides down a hill. The hill has a gentle 20° slope with respect to the horizontal. The block has an initial speed of 6 m/s. If the block comes to a stop after traveling a total distance of 11 m along the slope, what is the coefficient of kinetic friction between the...