Static friction Definition and 507 Threads

Problem 1: You need to move a 125-kg piece of furniture in your living room. You and your friend exert a force of 305 N to start it moving. What is the coefficient of static friction between the furniture and the floor? Problem 2: A 20-kg bowling ball slides half way down a lane with a...

Homework Statement If the coefficient os static friction between the incline and block is .3, then what is the minimum force,F, needed to prevent the block from sliding? m=20kg theta= 50 degrees Homework Equations Normal force= mgcosx Fs= uk mgcosx The Attempt at a Solution...

Homework Statement Block b with mass 5kg rests on block a with mass 8kg which in turn is on a horizontal tabletop. there is no friction between block a and the table top but the coefficient of static friction between block a and b is 0.75.A light string attached to block a passes over a...

A 2.0kg box rests on a plank that is inclined at a angle of 65 degrees above the horizontal. The upper end of the box is attached to a spring with a force constant of 360 N/m. If the coefficient of the static friction between the box and the plank is 0.22, what is the maximum amount the spring...

Homework Statement In about 1915, Henry Sincosky of Philadelphia suspended himself from a rafter by gripping the rafter with the thumb of each hand on one side and the fingers on the other side (Fig. 6-22). Sincosky's mass was 82.0 kg. If the coefficient of static friction between hand and...

Homework Statement Basically, I need to find the maximum static friction of my shoe against a wood board. I discovered that after increasing the slope of the board, my shoe slipped at an angle of 29.33 degrees. (using tan theta = O/A) O being 42.7 cm and A being 76 cm. The shoe has a weight...

Homework Statement The coefficient of static friction for wood on wood is 0.40, what mass would be required to overcome static friction of a 1.53 x 10^3 g block of wood on a wood table? Homework Equations I have absolutely no idea. The Attempt at a Solution I don't know. Thanks...

Homework Statement What is the minimum coefficient of static friction necessary to allow a penny to rotate without sliding off a 33.5rpm record (diameter of these old-fashioned records is 0.3), when the penny is placed at the edge of the record. Ignore the size of the penny. The Attempt at...

I did an experiment where I had to determine the static friction of a wooden block on a horizontal wooden plank. I determined Mu s for that to be 0.246 I then used the same block and plank, but this time I tried to determine Mu s by increasing the angle between the plank and the...

Homework Statement A 1200 kg car rounds a curve of radius 67 m banked at an angle of 12 degrees. If the car is traveling at 95 km/hr, will a friction force be required? If so how much and in what direction? Homework Equations F=ma a=v2/r The Attempt at a Solution I don't know what...

Homework Statement A box of textbooks of mass 24.5 rests on a loading ramp that makes an angle with the horizontal. The coefficient of kinetic friction is 0.260 and the coefficient of static friction is 0.360. As the angle is increased, find the minimum angle at which the box starts to...

Homework Statement A curve with a 135 m radius on a level road is banked at the correct angle for a speed of 20m/s. If an automobile rounds this curve at 30m/s, what is the minimum coefficient of static friction between tires and road needed to prevent skidding? Homework Equations...

Homework Statement A coin is placed on a record that is rotating at 33.3 rpm. If the coefficient of static friction between the coin and the record is 0.2, how far from the center of the record can the coin be placed without having it slip off? Homework Equations mv^2/r = mg(mu)...

Homework Statement This is a conceptual question. I always thought that friction goes in the direction opposite of the intended motion. But then today my teacher put a ball in his hand and moved it horizontally back and forth. The ball remained stationary. Then he said static friction is...

Homework Statement A platform on Earth rotates at constant angular speed 2 rad/s. A 60 kg man stands on the platform. Static friction between the platform and the man's feet prevent slipping. (a) Make a diagram showing the forces he exerts on the platform standing a distance r from the axis...

Homework Statement Hi, I'm having trouble with this question. I don't seem to get this at all. I hope you guys can help me on this. Before 1960, it was believed that the maximum attainable coefficient of static friction for an automobile tire was less than 1. Then, about 1962, three companies...

The coefficient of static friction between a block and a horizontal floor is 0.37, while the coefficient of kinetic friction is 0.14. The mass of the block is 3.4 kg. If a horizontal force is slowly increased until it is barely enough to make the block start moving, what is the net force on the...

Hello, I'm conducting an experiment about how contact force and surface quality affect friction. I know that friction is affected by both, as my data suggests. I measured the static forces of several weights on two different surfaces, and found that indeed the max static force increased as...

I am pretty sure the answer might be A. Can someone help by showing the work needed to solve the problem. It would be greatly appreciated Homework Statement A crate is carried in a pickup truck traveling horizontally at 15.0 m/s. The truck applies the brakes for distance at 28.7 m while...

Homework Statement A 200N crate rests on a ramp, the angle is 20 degrees with the horizontal. What is the coefficient of static friction between the crate and ramp surfaces Homework Equations T=N/cos theta The Attempt at a Solution 200/cos25 = 219 I don't know where to go from...

1. What is the minimum coefficient of static friction required for a roller-coaster car to complete a circular loop of radius r, if it is traveling with sufficient speed v? I'm just very confused with all of this because the question seems so broad and there are so many things to consider. A...

Homework Statement from the free body diagram of a block resting on a flat surface, I am trying to derive the coefficient of static friction. Homework Equations The Attempt at a Solution I have the definition of the coefficient as: us=Fn/Ffr But in my free body diagram i am...

Homework Statement A car traveling at 100 m/s enters an unbanked turn of 400 m radius. The coefficient of static friction between the tires and track is 1.1. The track has both an inner and outer wall. Which statement is correct? Homework Equations v=<square root>coefficientmgr/m...

Hello, the Force of static friction = Us*n , if i am given a Velocity then how do i find n (normal force)? There is no mass given just a velocity. I am not asking for help for a solution for homework, i am just asking for clarification. Thank you.

I'm sure that this is a very simple question, but I can't find it in my text. I made a few attempts but I see why they're incorrect, I just can't figure out the correct method. Homework Statement A flatbed truck is carrying a 60.0 kg crate along a level road. The coefficient of static...

Homework Statement A block is on a horizontal surface (a shake table) that is moving back and forth horizontally with simple harmonic motion of frequency 1.3 Hz. The coefficient of static friction between block and surface is 0.59. How great can the amplitude of the SHM be if the block is not...

A crate of mass 150.0 kg lies at rest on a horizontal storage room floor. The coefficient of static friction between the crate and the floor is 0.70, and the coefficient of kinetic friction is 0.35. (You may assume g = 10.0 m/s2). a) Suppose someone pulls on a horizontal rope attached to...

Homework Statement A 2.5 kg box in on a 53 degrees inclined plane. mu-kinetic = 0.25 and mu-static=0.5. Find it's acceleration if it is initially standing still. Homework Equations F = ma The Attempt at a Solution The X component of the gravity is = 2.5*g*sin(53) Normal force =...

Homework Statement A coin is placed 11.0cm from the axis of a rotating turntable of variable speed. When the speed of the turntable is slowly increased, the coin remains fixed on the turntable until a speed of 36rpm is reached and the coin slides off. What is the coefficient of static...

Homework Statement A small metal cylinder of mass m=0.20 kg sits on a rotating turntable. The coefficient of static friction between the metal cylinder and the turntable is us=.800. The cylinder is located 0.15m from the center of the turntable. Find the maximum speed that the cylinder can...

How would I find static friction given the following information: V= 45km/hr Time to decelerate completely from 45km/hr: 3.5s The motion of the object given is of a moving vehicle. There is a cup on the dashboard inside the vehicle that moves only when deceleration time is less than or...

this is a lab that I've been working on for 3 days alredy, and still cannot fill in the blanks for finding the coefficient of maximum static friction... a wooden block was attatched to a pulley connected to a hanger.. the wooden block was on top of a wooden board.. the goal was to add just...

Hi. During the completion of a physics lab i came across a problem. The lab consisted of putting a wooden block (0.10kg) at the en of a wooded board (1.84m), then lifting the wooden block side up slowly, so that when the block began to slide, we could record the hight. The problem is finding the...

This is from my physics lab.what we did was have a wooden block slide on a longer piece of wood that was laid flat on the table. the end of the wood had a pulley hanging over the edge of the table.hanging from the pulley was a hook and we had to see how much weight would get the wooden block to...

This is a problem from my Physics 101 class that I'm having trouble solving. I'm not sure what equations I'm supposed to use. Homework Statement To move a large crate across a rough floor, you push on it with a force F at an angle of 21° below the horizontal. Find the force necessary to...

Hi! I'm studying for an exam on Friday, and I'm stuck on this problem: A uniform chain of length 8.00m initially lies stretched out on a horizontal table. A. Assuming the coefficient of static friction between chain and table is 0.600, show that the chain will begin to slide off the table if...

Newtonian mechanics problem with blocks Problem: m_{1} and m_{2} each interact with m_{3} via static friction, with the same \mu_{s}. The horizontal surface below m_{3} is frictionless. An external force F_{ext} acts on m_{1} from the left and the entire system of three connected masses...

Homework Statement An object rests on an inclined plane. One end of the plane is lifted until the object begins to slide. If the angle at which the object begins to slide is 35 degrees, what is the coefficient of static friction? Homework Equations Possibly Fk=("mew"k)N The...

Homework Statement A 9 N horizontal force F pushes a block weighing 13.0 N against a vertical wall (Fig. 6-21). The coefficient of static friction between the wall and the block is 0.62, and the coefficient of kinetic friction is 0.42. Assume that the block is not moving initially...

Homework Statement A force of 48.0 N is required to start a 5.0 kg box moving across a horizontal concrete floor. (a) what is the coefficient of static friction between the box and the floor? (b) if the 48.0N force continues the box accelerates at 0.70m/sec2. what is the coefficient of...

My physics book shows the direction of static friction to be opposite to an applied force that is parallel to the surface in which an object rests with the same magnitude (if it is below or equal to its maximum value). If that is the case, when speaking about a car rounding a flat curve, why...

Homework Statement An astronaut is training in an earthbound centrifuge that consists of a small chamber whirled around horizontally at the end of a 4.5 m-long shaft. The astronaut places a notebook on the vertical wall of the chamber and it stays in place. If the coefficient of static...

An object of a mass "m" is held stationary on an incline plane at an angle "theta" by means of a rope attached to it. The rope is parallel to the incline. The coefficient of static friction between the mass and the incline is "mu_s". I assume the static friction force is up the plane to oppose...

My problem is: A coin is placed on a turntable that is rotating at 33.3 rpm. If the coefficient of static friction is .1, how far from the center of the turntable can the coin be placed without having to slip off? Am I correct with V= the 33.3 rpms? and that w (angular speed) =1.11 pi...

Homework Statement A car drives around a curve with radius 410 m at a speed of 32m/s. The road is not banked. The mass of the car is 1400kg. A. What is the frictional force on the car? B. Does the frictional force necessarily have magnitude μsN? Explain. Homework Equations...

Hey Guys, This is my first time posting ... sooo here it goes! I have spent the past hour trying to figure out how we walk (in a physics sense) - I can't seem to find anything good on google that really answers my question. I have a general idea that when i put my foot down, I push...

Homework Statement If the coefficient of static friction for a 5.0 kg rubber block on a floor is 0.72, how much force is needed to start it sliding? Mass=5.0kg Co-efficient of Static Friction=0.72 Friction=? Homework Equations coefficient of static friction = Friction Force/Surface...

Homework Statement A small box is resting on a larger box, which in turn sits on a table. When a horizontal force is applied to the larger box, both boxes accelerate together. The small box does not slip on the larger box. a)Draw a free body diagram of the small box as it accelerates...

Homework Statement I am given a right triangle with a block on it. At angle 18degrees the block does not move. At angle 19degrees the block starts sliding down the ramp. I am given no other information but I am told to find μS. The forces acting on the block are going to be Fn opposite the...

THE PROBLEM: A sports car is accelerating up a hill that rises 21.2 ° above the horizontal. The coefficient of static friction between the wheels and the road is μs = 0.880. It is the static frictional force that propels the car forward. (a) What is the magnitude of the maximum acceleration...