Coefficient of friction Definition and 416 Threads

I'm trying to measure the coefficient of friction between a wheel that weighs about 4 grams and a ping pong table. Are there accurate spring scales I can use to measure the force it takes to move the wheel? I'm estimate the force required to move the wheel to be in the thousands POUNDS (.00xlb)

Homework Statement A grindstone in the shape of a solid disk with diameter 0.520m and a mass of 50.0kg is rotating at 800rev/min . You press an ax against the rim with a normal force of 160N, and the grindstone comes to rest in 8.50s . Find the coefficient of kinetic friction between the...

Homework Statement When the converyor belt was first installed safety checks were carried out to determine the limit of angle for safety. It was found that at an angle of 30 degrees the crates start to slip down. Calculate the coefficient of friction between the crates and the belt? (Diagram...

Homework Statement Calculate the frictional force, normal force and coefficient of friction for an 0.2kg object that is lying on a 35 degree incline. Homework Equations Ff= u x Fn F= m x a The Attempt at a Solution I managed to get FN= m x a x cos# = -9.81 x 0.2 x cos35 = 1.61...

Homework Statement A 2 kg. block is pulled up a 22° incline with a force of 10N parallel to the incline. What is μ_{}k if it moves up with constant speed? Homework Equations F_{}N = Normal Force f_{}k = μ_{}k F_{}N The Attempt at a Solution Forces perpendicular to plane...

Homework Statement A truck weighing 15 tonnes is traveling down an decline of 15 degrees at 6.6m in 3s. He then stops and gets out. The truck then begins to roll down the decline as the brakes have failed. 1. What is the size of friction force acting on the rubber tyres of the charging vehicle...

Homework Statement The coefficient of friction is to be found from a skateboard and rider rolling down a ramp, which has an angle of 5 degrees. The skateboard accelerates at .5308 m/s^2. The mass of the rider and skateboard is 91.3 kg, or 895 Newtons. The other data would be gravity...

Homework Statement A 36kg girl slides down a slide that is 4.5m long. At the bottom of slide she is moving at 3 m/sec. If slide is inclined at 35 degrees find the coefficient of friction between slide and girl. Homework Equations Ff = μ*Force normal Total energy = KE + PE KE =...

Homework Statement The horizontal force P acts on the rim of the homogeneous cylinder of radius R and weight W. Determine the smallest coefficient of static friction that enables the cylinder to start rolling up the 30◦ incline. Homework Equations *depends on the fbd. refer below...

Not a question from a college course or anything like that, but one of interest to me:) You take a car tyre made of polyester and rubber, the treads are cut to about 7mm deep, the roads coefficient of friction are normally about 0.7 in conjunction with contact of the tyre, if the weight is...

Homework Statement What is the coefficient of friction of a block resting on a board at a 15° angle to the horizontal. Homework Equations μ= Fk Mg The Attempt at a Solution I'm very lost at where I find Fk or Mg...? Thanks for help in advance.

Homework Statement If a ball strikes a surface with an input velocity of 18m/s, incident angle 25 degrees, mass = 2.5kg, Coefficient of restitution 0.8 and Coefficient of friction 0.6 how would you calculate the output velocity and angle? I can work it out with restitution only but how do you...

Homework Statement A road with a radius of 74.8 m is banked so that a car can navigate the curve at a speed of 15 m/s without any friction. When a car is going 21.1 m/s on this curve, what minimum coefficient of static friction is needed if the car is to navigate the curve without slipping...

Homework Statement A block of mass 'm' is placed on an inclined plane which has an adjustable angle with the horizontal. The angle is increased slowly from zero until the block just starts to slide. This angle is called the critical angle, θs. Express the coefficient of friction in terms...

I am having trouble determining what the force of friction of the box on a table described as below: Two blocks are arranged at the ends of a massless string. M1 is on the table. M2 is attached to another side of the rope hanging off of the side of a table with a massless pulley (90 degrees...

*** Title says static - need kinetic friction!Homework Statement Find the amount of kinetic friction. A block with mass of 0.422kg slides down a ramp from rest. Given: acceleration = 1.58m/s^2, mass = 0.422kg, theta = 29.0°, velocity two (end): 1.7m/s, and total time is 1.10s. I also need to...

Homework Statement We have an investigative project and our group's topic is inclined plane surfaces. I need help in getting the coefficient of friction of the toy car. We will investigate the coefficient of friction of different surfaces. Our teacher didn't (and will never) discuss to us...

Homework Statement 1.a block of mass 5kg moves on a rough horizontal plane with coefficient of friction (Dynamic) 0.2 under the action of a horizontal force of 30N. If the block starts from rest , find the distance it travels in the first 3 second. 2.a particle of mass 6kg,moving at 8m/s on...

Homework Statement In the disc brakes that slow down a car, a pair of brake pads squeezes a spinning rotor; friction between the pads and the rotor provides the torque that slows down the car. If the normal force that each pad exerts on a rotor is 85 N, and the coefficient of friction is 0.62...

Homework Statement I have an almost-frictionless air-hockey style ramp and i place it horizontally on a table. A little cart goes on top and on one end of the cart, i attach a string which connects to a pulley and then connected to a weight, thus pulling the cart to one side with the force of...

Homework Statement a body of mass 10 kg lies on a rough horizontal surface with an acceleration of 5 m/s and when the horizontal force us doubled , it gets an acceleration of 18 m/s^2. Then the coefficient of friction between the body and the horizontal surface is: A) 0.2 B) 0.8 C)...

1. Homework Statement given: a large block ramp, a smaller block (one side wood, other side felt), and a stopwatch refer to this picture: http://01.edu-cdn.com/files/static/w...SLIDING_01.GIF you don't know weight, or θ but I do have the measurements for the x and y axis 2. Homework...

I'm really lost on how to do this physics problem because I don't really understand all the components of the problem: A 7.25 kg block is sliding at 5.45m/s on a frictionless lab bench which is 8.6m high. The block hits a 1m "rough patch" before sliding off of the lab bench, and then lands...

Homework Statement If the coefficient of static friction at B is μs = 0.3, determine the largest angle θ, and the minimum coefficient of static friction at A, so that the roller remains self- locking, regardless of the magnitude of the force P applied to the belt. Neglect the weight of...

1. A box of mass 28 kilograms is held at rest on a rough plane inclined at an angle of 60° to the horizontal by a rope attached to a vertical pole. When the rope is cut the box moves down the plane with an acceleration of a m/s^2. Find the expression for the coefficient of friction µ, in terms...

Homework Statement "A 1250 kg slipper hippo slides down a mud covered hill inclined at an angle of 18 degrees to the horizontal. A) If the coefficient of friction is 0.0900, what force of friction impedes the hippo's motion down the hill? B) If the hill were steeper, how would this affect the...

A() 61 kg child stands at the rim of a merrygo-round of radius 1.05 m, rotating with an angular speed of 1.87 rad/s The acceleration of gravity is 9.8 m/s^2 What is the child’s centripetal acceleration? Answer in units of m/s What minimum force between her feet and the floor of the...

If we set a ball rolling on a loop-the-loop track,why do we say that we need infinite friction coefficient for the ball to complete the loop. This seems illogical because f=kN. Since f and N are finite how can k be infinite ?

Homework Statement If a mass of 609 kg travels in a circle with a radius of 102 m, and the μ= .13, and the acceleration of gravity is 9.8 m/s^2. What is the max velocity that the mass can go without canceling out the force of friction? Homework Equations ? The Attempt at a Solution...

Hi everybody. I am going to exam on Monday. I would like to make a experiment on how to measure the coefficient of friction. I know, that I can find the mu(s), by taking the tan to the angle α. μs = tan(α). Is there somebody, who has some others ideas how to measure that? Somebody...

Homework Statement A box with mass 2kg is on the edge of a circular platform of radius 6.0m. The coefficient of friction between the platform and the box is 0.3. The platform accelerates. Determine the speed when the box slips off the edge.Homework Equations Fs = μsN F⃗ net=ΣF⃗ =ma⃗ a(t) =...

Homework Statement 1st problem: If and object has a weight of 100 N and a frictional force of 50 N exerted on it, what is the coefficient of friction? 2nd problem: A Block with a mass of 50 kg, is pulled with a force of 10 N at an angle of 10 degrees to the horizon, if the coefficient of...

Homework Statement A physics student slides a 2.0kg textbook along the laboratory bench to her friend. She imparts to the book an initial velocity of 2.70m/s. μ=0.20. How far away is her friend if the book comes to a stop right in front of her friend Vi= 2.70m/s μ=0.20 m=2.0kg Vf= 0m/s...

I need to find the coeffcient of friction on an incline plane. I need the equation to find the coefficient for any givien angle. It part of a lab where I'm required to create the procedure and am stuck with how to create the equation. We can use a protractor or trigonomic functions to find the...

A 10.2 kg block is being pulled at constant speed in the positive x-direction along a flat surface with which it has a coefficient of kinetic friction. It is pulled by a rope at an angle of 30° above the horizontal, and the tension in that rope is 50 N. Normal force is 75 N.

Ok so I'm in college upgrading, and doing my physics 20. I have a hand in assignment due Wednesday and I can't for the life of me figure out these two questions. 6. The 4.0kg block shown accelerates across a frictionless horizontal table at 1.5m/s2. Find the mass of object m1 A. 0.61kg B...

Homework Statement A 500kg box is being pushed across a floor, with an applied force of 8400N, at a constant velocity, at an angle of 35 degrees below the horizontal. What is the coefficient friction between the floor and the box. Homework Equations I really do not know where to...

An object on a 30 degree inclined surface with force applied up the ramp, weight of object = 6.9N, applied force on object = 3.13N My answer was -0.05, but I'm not sure if this is right so I want to make sure with someone's help Thanks

Hi, I'm doing research on the Coefficient Of Friction using a forceplate. I'm trying to determine the coefficient by pulling several objects over the plate, and using the frictional force and normal force to determine the coefficient of friction (measured by the force plate). When I pull...

Homework Statement A 100 kg bale of hay falls off a truck traveling along a level road at 24.4 m/s. It lands flat on the road and slides 100m before coming to rest. Assume the acceleration is constant, compute the coefficeient of kinetic friction between the road and the hay. Homework...

Homework Statement The Attempt at a Solution I found the acceleration using kinematics equations. I don't know how to find the coefficient of friction though. I need help answering pard b c and d If you could give me the equations and explain. Just knowing how to do this one...

Homework Statement A block weighing 9.3 N requires a force of 3.7 N to push it along at constant velocity. What is the coefficient of friction for the surface Homework Equations Ff=μ*Fn The Attempt at a Solution So the 3.7 N to push is the Force of friction so 3.7=μ*9.3...

Homework Statement An object is moved with a speed of 2m/s on one side of a 1m table to the other, it stops right at the other and of the table without falling off. Does it have wheels or not? Homework Equations The teacher gave this just to me and said we havnt learned about it yet...

Homework Statement A car is sliding down an icy hill inclined at 1.6 degrees, find the coefficient of friction. Homework Equations f_k=\mu_k*n The Attempt at a Solution Don't know how to begin it only given the angle of the hill.

This question this struck me as fairly simple until I repeatedly tried and failed to get the right answer so any help would be greatly appreciated. Homework Statement A block of mass 30 tonnes is to be dragged across the floor by means of the smaller body (mass 5 tonnes) acting through the...

Homework Statement Hi can anyone help me calculate the coefficient of friction between crates and a conveyor belt. The crate is moving up a 25O angle at a constant speed to a height of 12m. Homework Equations CoF=F/R The Attempt at a Solution I don't know if this is a trick...

Is it possible to find the coefficient of friction just by looking at a graph? A velocity-time or acceleration-time graph which models a particle going up a ramp and down a ramp.

Hi! A block with mass 35 kg is pushed upward with a horizontal force of 400N along a slope at an angle of 30 °. The block makes a displacement of 2 meters, where it's speed changes from 1m/s to 1,8m/s. What is the Coefficients Of Friction? 1) 0.312 2) 1.099 3) 0.039 4) 1.31...

Homework Statement Prove mathematically that the coefficient of friction is independent of the mass of a rider at a fixed location from the center on a merry go round. Homework Equations F = ma? The Attempt at a Solution I honestly don't know - I can't find two starting equations...

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...