Coefficient of friction Definition and 416 Threads

Hi all *Pls can somebody tell me why clutches and brakes need high coefficient of friction *also i need applications where engineers need to have materials having low values for the coefficient of friction Thanks

Homework Statement A car moving at 5 m/s tries to round a flat corner that has a radius of curvature of 8 m. How large must the coefficient of friction be between the wheels and the roadway if the car is not to skid? Homework Equations mv^2/r i don't know anything else. Fc=Fn(mk)...

I have some very small spherical particles with diameter of 1 mm and i would like to know coefficient of friction between them. Can anyone suggest an experiment/device that would help me? In order to get friction between a plate and particle i can use tilt test and measure the angle at which...

How do you find the minimum coefficient of friction needed to prevent slipping for part a and part b. A hollow spherical shell of mass 4.00 kg rolls without slipping down a 38.0° slope. (a) Find the acceleration. 3.62 m/s2 Find the friction force. 9.64 N Find...

A boy pulls a sled of mass 5kg with a rope that makes an angle of 60 degrees w/ respect to the horizonal surface of the frozen pond. The boy pulls on the rope with a force of 10N and the sled moves with constant velocity. What is the coefficient of friction between the sled and the ice...

Homework Statement A 51kg child goes down a 42 degree slide. What is the normal force on him? If the coefficient of friction is .10, what is the net force on him? How far down does he slide before reaching 2.5 m/s?Homework Equations Fk = μFn F = ma The Attempt at a Solution Fn = 51gcos(42)...

Homework Statement A 3000kg cannon fires a 14 kg shell horizontally with a muzzle velocity of 450m/s. The cannon recoils for a distance of 2.5m before coming to a stop. What is the coefficient of friction between the cannon and the ground that it rests upon? mcannon= 3000kg mball=14kg...

Homework Statement a boy uses a rope to pull a box weighing 300 Newtons across a surface with a constant velocity . The rope makes an angle of 30 degrees with the horizontal, and the tension in the rope is 100 Newtons. What is the coefficient of friction ?? The Attempt at a Solution...

Homework Statement An ice skater moving at 10.0 m/s coasts to a halt in 1.0 x 10^2 m on a smooth ice surface. What is the coefficient of friction between the ice and the skates? Homework Equations coefficeint of friction = kinetic friction/Normal force (µk = Fk/Fn) Σ Fy = may Σ Fx...

Homework Statement A 50.2 kg object begins to slide down a 32 degree ramp. What is the coefficient of friction for this ramp? What is the objects acceleration down the ramp? If the object is 2.51m from the bottom of the ramp, what will be its final velocity? How long does it take for the...

a block weighting 5.6N requires a force of 3.8N to push it along at constant velocity. What is the coefficient of friction for the surface?

1. A 50 kg Skater pushes off horizontally for a distance of 0.4m with a force of 150N. If she travels 80m before stopping, what is the coefficient of friction? I am completely lost on this problem, can someone please assist me? Thanks.

Does anyone know the coefficient of friction between the vaginal wall and the penis?

Homework Statement A wedge slides down a frictionless inclined plane that makes angle with the horizontal. A small block is placed at the horizontal top side of the wedge. During the slide, the block does not move relative to the wedge. Find the minimum possible coefficient of static friction...

Homework Statement It says: A 20kg object is placed on a horizontal surface. A force of 3N is required to keep the object moving at a constant speed. What is the coefficient of friction between the two surfaces? I figured that we know that Ff=uFn and Fn=Fg=mg therefore Fn=20*9.8=196N That's...

I need to find the coefficient of friction and the angle of an incline with only knowing a distance of 18.0 meters and a time of 10.0 seconds. I have absolutely no idea where to begin because my teacher never taught us how to do such equations. if anyone can figure the problem out for me that...

Homework Statement A person slides to third base. The coefficient of kinetic friction between player and the ground is 0.70. His velocity at the start of the slide is 8.23m/s [forward]. Prove that the time it takes the player to come to a stop from sliding is: time = initial velocity divided...

Homework Statement A student has two ramps, both of which are at an angle of 30o. Ramp 1 is frictionless and ramp 2 has friction. The student also has two blocks, one for each ramp. She pushes the blocks up the ramps with the same initial velocity. The block on ramp 2 only travels a...

A initially stationary block of mass "m" is on the floor. A force of magnitude 0.500mg is then applied at upward angle 20 degrees. What is the magnitude of the acceleration of the block across the floor if coefficient of static friction = 0.6 and coefficient of kinetic friction = 0.5? i...

Homework Statement If the kinetic coefficient of friction between ice skates and ice is 0.01, what is the average forward force necessary for a 500 Nt skater to maintain a constant forward velocity? Homework Equations f = (Uk)(N) The Attempt at a Solution f = (Uk) (N) f = (0.01)...

Ok, i have a question that i need someone to put into simple terms, i kind of understand why, but it would be helpful if someone could explain it more simply. How does the coefficient of friction associated with starting an object's motion compare to the coefficient associated with...

A 20.0kg sled is being pulled across a horizontal surface at a CONSTANT VELOCITY. The pulling force has a magnitude of 80.0 Newtons(N) and is directed at an angle of 30 degreesabove the horizontal. What is the coefficient of kinetic friction?

How do you find the coefficient of kinetic friction?

Homework Statement Consider the carnival ride in which the riders stand against the wall inside a large cylinder. As the cylinder rotates, the floor of the cylinder drops and the passengers are pressed against the wall by the centrifugal force. Assuming that the coefficient of friction...

Homework Statement The question asks me to work out the coefficient of friction for a block accelerating down a rough slope assuming their is no air resistance, which I could do easily. In the next part it then asks how the coefficient would change if their was air resistance Homework...

Homework Statement I was reviewing some questions from the NYS Regents Physics exam and came across this question, which I could not answer. Here's the question ... An 80-kg skier slides on waxed skis along a horizontal surface of snow at constant velocity while pushing with his poles...

Homework Statement calculate the final velocity of an object sliding across a surface with a coefficient of friction of 0.2, a distance of 3m, an initial velocity of 50m/s and the object's mass of 100kg. μ=0.2 v1= 50m/s d=3m m=100kg v2= ? Homework Equations I know F= μ*normal...

If an object slides down a slope at a constant speed is the coefficient of static friction the same as the coefficient of dynamic friction? If yes, is this true in every situation?

Homework Statement A 135 kg sled is being pulled along a horizontal surface at a uniform speed by means of a rope making an angle of 19.3 degrees with the horiontal. If the tension in the rope is 119 N Find the Coefficient of friction. Homework Equations u=Ff/Fn The Attempt at a...

What is the coefficient of friction for a metal mass sliding down a wooden slope? Mass=0.50kg Slope distance=1.83m Angle=54 Degrees Time=1.06 s Vi=0m/s g=9.81m/s/s For this question we had to write out a formula and find mu. I first found acceleration to be 3.257m/s/s, Friction force to be...

Homework Statement It's a snowy day and you're pulling a friend along a level road on a sled. You've both been taking physics, so she asks what you think the coefficient of friction between the sled and the snow is. You've been walking at a steady 1.5 m/s, and the rope pulls up on the sled at...

Homework Statement We have two block of mass that rest upon each other. A force is applied to the top block and that cause both of the blocks to accelerate at different rates. What are the coefficient of friction needed to achieve this, assuming that bottom block rest on a frictionless...

Homework Statement Ben pushes a box along a floor against a constant force of friction. When Ben pushes with a horizontal force of 75N the acceleration of the box is 0.5 m/s/s; when he increases the force to 81N the acceleration is 0.75m/s/s. Homework Equations Find the mass of the...

Homework Statement Block A is on a table and is connected by a pulley to block B. Block A has weight Wa and block B has weight Wb. Once block B is set into downward motion, it descends at a constant speed. Assume that the mass and friction of the pulley are negligible. Calculate the...

Homework Statement A car traveling on a flat (unbanked) circular track accelerates uniformly from rest with a tangential acceleration of 1.80 m/s2. The car makes it one quarter of the way around the circle before it skids off the track. Determine the coefficient of static friction between...

Homework Statement You are pushing a filing cabinet across a rough floor (μk = 0.41) in a straight line at a constant speed. Which of the following statements about the magnitudes of the forces acting on the filing cabinet are correct? (T/F)the force that you exert on the filing cabinet...

This is the concept that I am understanding for coefficient of friction. Static coefficient of friction is one which refers to friction which is considered when the object is stationary relative to the other contact object. Kinetic coefficient of friction is one which refers to the friction...

a) A block weighing 9.1N requires a force of 2.8N to push it along at constant velocity. What is the coefficient of friction for the surface? b) A weight "W" is now place on the the block and 8N is needed to push them both at constant velocity. What is weight "W" on the block? This is what I...

Hi, Does air flow along a surface with a lower coefficient of friction more easily or does it not make a difference?

Homework Statement If a force of 45 Newtons is needed to overcome friction and the coefficient of friction=0.26, what is the mass of the object? The Attempt at a Solution So would I need to find the frictional force first? But then I can't use the equation: (frictional...

This problem is quite difficult for me. I know that there's a way to do this, but i can't figure it out. Could someone point me in the right direction? i don't need a solution, but a process would be nice. Homework Statement A box is given an initial push so that it slides across the floor...

A flatbed tractor trailer takes off from a stop sign on a level road. If a box on the back slides back 10 meters while the truck goes forward 50 meters and attains a speed of 15 m/s, what is the coefficient of friction (μ) between the bed and the box? Assume the bed to be at least 10 meters...

Homework Statement A train moves on a straight track at y degrees to the horizontal. The mass of the train is 1000kg. during its motion the train moves under the action of a variable propulsive force, p Newtons, and a constant resultant forceR Newtons (a) during the first stage of motion...

Homework Statement 1. A childs slide is straight and inclined at 25o to the horizontal. Matthew of mass 35kg goes down the slide at a constant speed. (a) draw a diagram (b) find the magintude of normal reaction force between matt and slide. (c) Find the coefficient of friction between...

Homework Statement A 1676 g mass is on a horizontal surface with mu-k = 0.340, and is in contact with a massless spring with a force constant of 508 N/m which is compressed. When the spring is released, it does 9.17 J of work on the mass while returning to its equilibrium position...

Homework Statement A large block with mass 30 kg executes horizontal simple harmonic motion as it slides across a frictionless surface with a frequency of .75 Hz. A smaller block with mass 10 kg rests on it, as shown in the figure, and the coefficient of static friction between the two is...

Homework Statement A rubber Eraser is placed on a cardboard record on a turntable. The turntable is set to 33 1/3 rotations per minute. what is the max radius for the eraser to be placed without slipping. but first calculate the coefficient of friction. You will not be given mass or radius of...

Homework Statement A horizontal force of 2N is just sufficient to prevent a block of mass 1kg from sliding down a rough plane inclined at arcsin 7/25 (=16.3 degrees) to the horizontal. Find the coefficient of friction between the block and the plane and then acceleration with which the block...

Homework Statement This is sort of a multi part question which had us do a lab. We did the lab and got numbers, and from this we have to make an equation to find exact values that we could use to find the angle for which a block can be pulled, with a certain coefficient of friction, that the...

Homework Statement A person of mass 60kg standing on a horizontal floor attempts to push a large wheeled crate of mass 800kg, which can roll on the same horizontal floor with coefficient of rolling friction equal to ur=0.03. What is the minimum coefficient of friction required between the...