All Questions
Tagged with rotational-kinematics friction
58
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When a wheel begins to roll on a flat surface, is it due to fulcrum generated at the contact point by friction?
[Edit: What I'm trying to understand is how any wheel rolls on a surface, instead of just spinning in place. I know that friction provides the force to make the wheel roll, but I'm unsure about the ...
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2
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Energy loss due to friction in Rolling Motion
I understand why rolling motion does no work. My (possibly imprecise) summary of the answer is that net work done is zero. And the role of friction is to convert translational kinetic energy into ...
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Calculating moment of inertia for a hollow cylindrical shell of varying amounts of water within it for an experiment about rotational motion [closed]
I am doing an experiment with the overall research question of: To what extent does the amount of fluid within a hollow cylindrical can affect its dynamics while rolling down an inclined plane
I was ...
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3
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Doubt: (For pure rolling motion and friction)
For pure rolling motion, at the point of contact of the wheel at the ground the net velocity is 0, so there is no relative motion. But if at that instant no relative motion, then how can static ...
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Is accelerated rolling with slipping possible?
I have a conceptual question regarding the following tasks. Two cylinders with different coefficients of friction are rolling down a inclined plane, thus accelerating. According to the task, due to ...
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1
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Is friction equal to gravitational force during rolling down a ramp?
I'm studying the motion and forces involved in a ball (bidimensional) rolling down a ramp inclined by an angle $\theta$ from the x-axis.
This is the body diagram (I didn't draw forces but there is ...
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108
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No-circular motion on a turntable
As the title says, I want to model the path of an object sliding on the surface of a turntable, as it is slowly flung off.
The final application of this is , modelling fine material moving along the ...
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1
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862
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What does neglect friction mean?
According to my teacher, neglect friction means to neglect the work of friction. I believe that it means that the system is frictionless. Am I wrong?
The problem is specifically, "A 5 kg cylinder ...
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1
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Can a torque on the rim of a solid cylinder cause rolling without slipping?
I'm getting stuck on friction (heh). Here's a simplified problem from my textbook illustrating my confusion.
We have a solid cylinder of mass m and radius r, lying on its side on a table, with a ...
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3
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Why is the direction of friction different in case of rolling on plane surface and on an inclined plane?
I was studying the rolling of spherical objects on plane surfaces and inclined planes. I had doubts about the direction of friction in both cases.
Case 1-
In the first case i.e. rolling on the plane ...
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Rotational Motion (Axe and Grindstone) [closed]
You have a grindstone that is 90.0kg, has a radius of 0.34m and is turning st 90 rpm. You press a steel axe against it with a radial force of 20.0N. Assuming that the kinetic coefficient of friction ...
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If an object stays afloat in air for long enough, will it start moving backward eventually? [duplicate]
Let's say, for example, if a helicopter that has an unlimited fuel supply and everything else needed to stay functional stays afloat in air for long enough, would it eventually start moving backwards? ...
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Is there a physics explanation for why dry steering damages tyre?
I used to think dry steering damages tyres because static friction takes place when the car is not moving, as opposed to dynamic friction when the car is moving. (Note: static friction has greater ...
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2
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Rolling without slipping, where is the friction?
Consider a ball rolling without slipping on a horizontal surface. Obviously it is going to stop at some point, but why? Since the surface of the ball that is in contact with the surface of the floor ...
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Friction during rolling
I have four doubts regarding friction during rolling.
Does slipping mean zero angular velocity, or is it just the $v$ velocity not being equal to $\omega r$?
If a wheel is initially given the ...
user287374
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Question about rolling and slipping of a cylinder for example down an inclined plane
What is the point at which sliding occurs?
I know sliding is when the $V_{cm}$ goes faster than the point of contact on the ground. But I've been reading that sliding occurs when the total torque on ...
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How to judge direction of motion?
I have this scenario
suppose a cylinder is made by joining two symmetrical cones and is given a gentle push on two rails A and B . What will be the motion of cone . Will it turn right or left
I ...
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Wheel slips and weight
With rainy season starting, I have been thinking about traction and have a question:
Question: If two identical vehicles, one of mass $m$ and the other of mass $2m$ are starting from rest with equal ...
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4
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550
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Direction of friction of a rotating ring/disk
I'm trying to understand friction but I'm getting a bit confused...
If I have a ring rotating on the ground around its COM what is the direction of the friction?
If I have the same ring, but this time ...
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363
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The ball-in-cylinder problem I've encountered
This is going to be one of the most childish questions ever asked on this site but hear me out.
Today, as I'm fiddling around with balls and toilet rolls (as one does), I found something interesting ...
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Conservation of energy of 2 identical Rolling Disks with and without friction
My physics book claims that if two identical disks moving at the same velocity travel up nearly identical hills, with the second hill not having friction, then the disk rolling up the first hill will ...
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4
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Conservation of angular momentum and collision [closed]
The problem:
Consider a thin ring rolling without slipping (pure rolling) on a rough surface (means there is friction) with constant velocity $v_0$. The ring hits a vertical wall elastically and ...
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1
answer
34
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How far a sphere will move if we stick smaller sphere at different positions
There is a big sphere of mass M and radius R, and a small sphere with mass m and radius r. Now smaller sphere is stuck at a certain height and angle $\theta$.
The ball would roll to some distance. I ...
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Rolling race where objects roll with slipping
One of the interesting demonstrations of Moment of Inertia includes the "Rolling Race" where objects of same mass and radii but having different Moments of Inertia, are allowed to roll down ...
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How friction force synchronize linear velocity and angular velocity? [closed]
I am doing a simulation about moving balls on a surface. There are frictions between different balls and the surface. In the beginning, balls have a linear velocity and an angular velocity (which are ...
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Horizontal component of velocity in case of rolling
I was having a hard time to understand that the point of contact in case of rolling without sliding has zero velocity. So after some research, I posted my understanding as an answer How can the ...
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Work done by static friction in Rolling
In rolling without slipping, I understand that the velocity of the point where static friction with the ground is 0, and therefore static friction cannot do work. However, from newtons laws, an object ...
user225234
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3
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Is there a reference frame in which the static friction from rolling does positive work?
I am worried this will be deleted as a duplicate question, so I will try to be extra clear what I am asking:
In some reference frames, static friction can do positive work. If you have a crate in the ...
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239
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how does a car move? and how do the brakes affect its velocity? [duplicate]
im doing a project that requires me to understand how cars move. from what I understand , its the friction that is creates in the tires that enables the tire to rotate, which then push the car forward....
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701
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Billiard ball with side spin
A cue ball is travelling along a snooker table. Initially, it has only side spin (yaw). As it travels it will develop a rolling spin (pitch).
Can the ball develop any (roll) and thus move off the ...
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Why do office chairs rotate when pushed/pulled out?
A common source of frustration when I'm at work is the fact that my rolling office chair's wheels rotate whenever I push it forward or backward from my desk, which can cause it to bump my computer ...
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3
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Why does friction not accelerate a wheel?
It seems like a silly question because this defies common sense, but it appears that friction is supposed to accelerate a wheel (not attached to anything).
We can derive from Newton's laws that $\...
user113773
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Why should the friction between two disks be zero when there velocity is same? [duplicate]
In this video here, Walter Lewin mentions two discs of different radius $r_1$ and $r_2$, of the same density, where the first disk is initially rotating, while the second is at rest. In the videos ...
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The path of a disk/cylinder with translation and rotation [closed]
The conditions:
We have a regular disc of mass $\mathrm{M}$ and radius $\mathrm{R}$. It is placed on a horizontal plane with friction (which is constant throughout). It is then given an initial ...
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2
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686
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Friction during ball backspin and overspin
I already know sliding friction of ball on a flat table and rolling resistance of it.
How do I know coefficient of friction value when the ball has backspin with some angular velocity $\omega$? And ...
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138
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Bearing spinning longer Horizontally
While performing a physics experiment, a fidget bearing was held horizontally, while spinning, and held vertically. The same torque was applied vertically, as well as horizontally on the bearings' ...
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In which case will the kinetic energy be more after reaching the bottom? [closed]
In which case will the kinetic energy be more after reaching the bottom? The shaded surface have friction and other are smooth.
I thought about these questions:
Does the answer depend on whether ...
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Why does it get harder with time, to rotate a screw with a screwdriver?
A couple of forces act on the machine screw and create the turning effect. But after sometime it gets harder. So, net torque is decreasing, but why is it decreasing? Frictional force comes into action,...
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Why does no slipping occur when a particle is attached to a string, which is wound onto a circular disk, and the system is allowed to move?
In this question, the only way we can find the angular acceleration of the disc is by equating it to the linear acceleration of the particle divided by the radius. But this holds only if the string ...
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876
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Why does a car moving at a roundabout move off in a tangent?
In the case where a car is inn circular motion at a roundabout, it moves off in a tangent when its speed surpasses the maximum speed. I understand why such tangential motion happens in the case of a ...
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Rotational mechanics for ball
I got two questions
1)in pure rolling motion is angular acceleration and angular velocity same for a ball about its centre of mass and about its point of contact with ground?
2)if a ball is placed ...
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1
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221
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Barrel Rolling on concrete reverses its direction of motion
While reading my textbook I came across an activity which told :
Try rolling a barrel from concrete onto grass, what happens does the barrell reverses its direction of motion ? Is this because of ...
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2
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Direction of frictional force on a particle on a plate in circular motion
If we have a particle on the surface of a round plate ,at a distance $r$ from the center, that is rotating with an angular acceleration $k$ , and this particle is in equilibrium with respect to the ...
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Friction & relative motion
If there are two bodies that have zero relative velocity, does that mean friction will not exist between them, since friction opposes relative motion. In the figure below i have two wheels A&B, ...
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In which direction does friction from the ground act on the wheel?
When a bicycle wheel is in motion, many forces are acting on it. The sum of the forces results in forward
motion. In which direction does friction from the ground act on the wheel?
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The direction of frictional force in circular turning
Why does the frictional force in case of circular motion point towards the center even though the motion is tangential to the radius?
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Problem on rotation
So this is the problem:A wheel of radius of gyration k is placed on a belt moving with a speed v, which is maintained constant by means of an external agency. Assume that the axis of the wheel is ...
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2k
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Question about friction in rolling without slipping?
I was under the impression that for a ball/cylinder to roll without slip, there must be a static friction force that opposes the direction of motion. Why, in this case, does the friction act in the ...
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Why does an ice hockey stick, when thrown on ice always rotate and translate together before coming to rest? Why not only rotate or only translate?
When a hockey stick is thrown on ice it simultaneously rotates and translates before stopping. Friction probably plays the main role here, along with the shape of the stick. I think maybe it is due to ...
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Intuition for why friction on rolling objects is in the same direction as motion?
When we usually draw friction, it is opposite the direction of motion. However, in rotational motion problem when a cylinder is rolling on the floor, it is in the same direction as the motion. I did ...
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