Rolling is a type of motion that combines rotation (commonly, of an axially symmetric object) and translation of that object with respect to a surface (either one or the other moves), such that, if ideal conditions exist, the two are in contact with each other without sliding.
Rolling where there is no sliding is referred to as pure rolling. By definition, there is no sliding when there is a frame of reference in which all points of contact on the rolling object have the same velocity as their counterparts on the surface on which the object rolls; in particular, for a frame of reference in which the rolling plane is at rest (see animation), the instantaneous velocity of all the points of contact (e.g., a generating line segment of a cylinder) of the rolling object is zero.
In practice, due to small deformations near the contact area, some sliding and energy dissipation occurs. Nevertheless, the resulting rolling resistance is much lower than sliding friction, and thus, rolling objects, typically require much less energy to be moved than sliding ones. As a result, such objects will more easily move, if they experience a force with a component along the surface, for instance gravity on a tilted surface, wind, pushing, pulling, or torque from an engine. Unlike cylindrical axially symmetric objects, the rolling motion of a cone is such that while rolling on a flat surface, its center of gravity performs a circular motion, rather than a linear motion. Rolling objects are not necessarily axially-symmetrical. Two well known non-axially-symmetrical rollers are the Reuleaux triangle and the Meissner bodies. The oloid and the sphericon are members of a special family of developable rollers that develop their entire surface when rolling down a flat plane. Objects with corners, such as dice, roll by successive rotations about the edge or corner which is in contact with the surface. The construction of a specific surface allows even a perfect square wheel to roll with its centroid at constant height above a reference plane.
Hey all,
I'm stuck on this problem and not sure how to proceed/if I'm in the right direction.
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(A) find the direction...
Homework Statement
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Homework Statement
A force(Fi) is acting on the top point of a disc of radius r and mass m. The disc is rolling without slipping. Angular velocity of disc after center has been displaced distance x is?[/B]Homework Equations
Energy conservation; Moment of inertia of disc (MR^2)/2
The Attempt...
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Greetings, mechanical engineers of Physicsforums,
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The Attempt at a Solution
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Homework Statement
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Homework Statement
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Homework Statement
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Homework Statement
A bowling ball rolls without slipping up a ramp that slopes upward at an angle β to the horizontal. Treat the ball as a uniform solid sphere, ignoring the finger holes. Explain why the friction force must be directed uphill.
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Homework Statement
A 1 kg ball with a radius of 20 cm rolls down a 5 m high inclined plane. Its speed at the bottom is 8 m/s. How many revolutions per second is the ball making when at the bottom of the plane?
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Homework Statement
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Homework Equations
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Homework Statement
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Homework Statement
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Homework Statement
Which statement concerning a wheel undergoing rolling motion is true
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Hi everybody, I know this problem has been posted before, but it envolved Lagrangian methods which I haven't seen yet. I would appreciate any help.
1. Homework Statement
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Homework Statement
A uniform solid sphere, of radius 0.20 m, rolls without slipping 6.0 m down a ramp that is inclined at 28° with the horizontal. What is the angular speed of the sphere at the bottom of the slope if it starts from rest?
Homework Equations
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Hi everyone, this problem involves smooth rolling and translational motion:
1. Homework Statement
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Hi everyone, I've been working on this problem for a while now, and I was hoping someone here could point me in the right direction. Here goes:
1. Homework Statement
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Hey PF readers,
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Homework Statement
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Homework Statement
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Homework Statement
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Homework Statement
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Homework Statement
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I guess:
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Homework Statement
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Homework Statement
In this problem, we will demonstrate the Central Limit Theorem by a virtual test that involves
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Definition/Summary
"Rolling" means moving along a surface without sliding.
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Homework Statement
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Homework Statement
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Help me to understand my physics homework
Suppose if a ball is rolling down in an inclined plane, what happens to the normal force acting on it? How to understand the Normal force in this situation
Please explain
Thanks