The solution is also attached. I understand everything here except for part (b). What I don't get - why is it that when the ball starts rolling without slipping, we use moment of inertia about the point of contact instead of about the center of mass; and why is it that when the ball starts...
If we had a wheel rolling without slipping down the inclined plane, kinematically its velocity would be 0 at the contact point to the ground since the rotational and translational components of velocity would cancel out.
Speaking of forces, forces acting on body would be static friction and...
Given that there is a cylinder rolling without slipping down an incline, the method I was taught to represent the KE of the cylinder was:
##KE_{total} = KE_{translational} + KE_{rotational}##
##KE_{total} = \frac {1} {2} mv_{cm}^2 + \frac1 2 I \omega^2## Where "cm" is the center of mass, and...
Consider an object, say a ball, rolling at a constant speed without slipping to the right on a horizontal surface. Let's consider the ideal case, so no deformation of ball or surface. For rolling without slipping to occur, there has to be friction (static friction as the point on the ball that...
a) From impulse-momentum theorem I have: ##J=mv## so ##v=\frac{J}{m}## and since the ball doesn't slip ##v=\Omega b## so ##\Omega=\frac{J}{mb}## and ##\dot{\theta}=\frac{v}{a+b}=\frac{\Omega b}{a+b}##.
b) I considered the angular impulse: ##-J(a+b)=I_0 \Omega_0 \Rightarrow...
The acceleration and velocity of a body rolling down without slipping on a frictionless inclined plane are given by
$$
a=\dfrac{mg\sin \theta }{m+\dfrac{I}{r^{2}}}=\dfrac{g\sin \theta }{1+\dfrac{K^{2}}{r^{2}}} \cdots(1)
$$
$$...
So I tried the problem and it’s different from the solution. I’m confused on why my attempt didn’t work, is it because the wheel is undergoing general planar motion? I tried to just apply Newton’s 2nd law to find the acceleration of the centre and then use that to find angular acceleration. The...
I don't know how to start it
Is the truck who make the cylinder roll, initially? If yes, how? Since the truck force would pass by the center of the cylinder.
Therefore, if someone were to ask what the magnitude of centripetal acceleration is at the top of the wheel at a given instant (relative to the ground):
##v_{cm} = v_{translational, center-of-mass/wheel}##
##ω = ω_{point-of-contact}##
##v_{top} = 2(v_{cm}) = 2(rω)##
##a_{c(top)} =...
Hi
If a rigid disc rolls down an incline plane without slipping then the component of weight down the plane causes the disc to accelerate downwards but the frictional force causes a torque which causes the disc to rotate, At the point of rolling without slipping the velocity of the centre of...
Firstly, I need to determine what the electric field is causing.
Using left hand rule, the force due to the field is acting down the slope.
Hence my FBD looks like:
Where the two arrows pointing towards the right represent the force due to the field and weight of the cylinder.
Since ...
Ok so please bear with me here and what is almost certainly a really stupid question, partly because I don't quite know how to ask it.
When you have a wheel such as one attached to a car, a torque is applied to it from the engine. It's my understanding that the wheel would slide over the road...
Problem Statement: Let there be a ring of mass m and radius r. Let 3 masses be attached to the ring and named as O,P and Q. Mass of O and Q is 2m and mass of p is M. The angle between 2 masses is 15 degrees as shown in the figure.
Find the maximum velocity the ring must roll so that it doesn't...
Homework Statement
A mobile disk of radius R and mass M is moving above another immobile vertical disk of the same radius.
Initially the mobile disk is at rest at the highest point above the immobile disk and then it starts rolling without slipping. Assuming the mobile disk never slips, find...
Homework Statement
A thin spherical shell is sliding with velocity ##v_0## on a table initial until friction eventually causes it to roll without slipping. Find its translational velocity when the it rolls without slipping as a fraction of ##v_0##.
Homework Equations
$$I=\frac{2}{3}MR^2$$...
in case of rolling without slipping of a solid sphere having uniform mass density the condition is
Vcm (velocity of center of mass ) = Rω or [a][/cm] = Rα ,which comes from the fact that if an object that rolls without slipping the geometric center of the body travels 1 circumference along...
Homework Statement
The marble rolls down a track and around a loop-the-loop of radius R. The marble has mass m and radius r. What minimum height h must the track have for the marble to make it around the loop-the-loop without falling off? (Use any variable or symbol stated above along with the...
Homework Statement
A bowling ball sits on the smooth floor of a subway car. If the car has a horizontal acceleration a, what is the acceleration of the ball? Assume that the ball rolls without slipping.
Homework Equations
torque = R x F = Iα
aball= Rα
Isphere = (2/5) MR2
The Attempt at a...
Homework Statement
A sphere of radius R is rolling without slipping with a velocity v and collides inelastically with a step of height h < R. ¿What is the minimum velocity for which the sphere will be over the step?
Homework Equations
Total kinetic energy (maybe)...
Homework Statement
Homework Equations
3. The Attempt at a Solution
These are my two observations for this problem .
1) Center of mass of the ring moves in a circle of radius (R-r) about point O . O is the center of the smaller circle in figure 2 .
2) From the geometry , the angular speed...
Homework Statement
I am solving a question that asks for, what's the minimum coefficient of friction required for a cylinder to roll without slipping? Where the cylinder has a force F acting on its center.
Homework Equations
And
The Attempt at a Solution
From the way I understand it, the...
Homework Statement
A solid spherical ball of mass 0.75 kg and radius 5.0 cm is thrown onto a horizontal surface with coefficient of kinetic friction μ . It’s initial velocity at time t = 0 is horizontal and its initial angular velocity is zero. After rolling with slipping for a time t1 = 0.76...
Can someone please help me out with this tough problem?
1. Homework Statement
A ball rolls on a turntable without slipping describe the balls motion in terms of (x,y) for a function of time. (The turntable spins at a constant rate)
(This all the information that the professor gave us.)The...
I am sorry for drawing up very old and closed posting https://www.physicsforums.com/threads/rolling-friction.150891/
but I saw this question many times and I can not understand why do not people simply use well-known theorem which says that power of the forces which are applied to a rigid body...
Imagine a hoop with mass M and radius R that will only roll without slipping on the floor. Place a point object with mass m on top of the hoop and then the system starts from at rest. Question: where does m leave M?
If one fixes the hoop or let the hoop slide, solutions can be found using high...
Homework Statement
[/B]
I have two cylindric reels laying on the ground. They are identical: mass M, composed by a cylinder of radius R and two side cylinders of radius 2R. I have to find angular acceleration and work done by F in delta t.
2. The attempt at a solution
On the first cylinder...
I'm confused about this rolling without (or better with) slipping situation. Suppose to have a disk with initial velocity ##v## and angular velocity ##\omega##. The motion is to the right but the angular velocity is counterclockwise.
There are no forces acting on the disk besides the kinetic...
<<Mentor note: Thread split from https://www.physicsforums.com/threads/torque-opposite-in-direction-to-change-in-angular-momentum.866882/>>
it can be proved that in this case pure rolling without slipping is impossible
ive assumed the cone to be right circular
proof by contradiction...
I have a doubt regarding the definition of rotational work, which is as follows
W = \int \tau_z d \theta
Where \tau_z is the component of the torque parallel to the axis of rotation z.
My doubt concerns the fact that, looking at this definition, it seems that any torque which has an axial...
Homework Statement
Rolling without slipping
A) Derive the linear acceleration vector equations for points A, B, C, and O in terms of R, ω, α and θ at this instant.
B) R = 0.5 m, ω=-54 r/s and α = 0. Determine the MPH of the vehicle and the vector accelerations of points A, B, C, and O.
C) R...
Homework Statement
[/B]
A thin light string is wrapped around a solid uniform disk of mass M and radius r, mounted as shown. The loose end of the string is attached to the axle of a solid uniform disc of mass m and the same radius r which can roll without slipping down an inclined plane that...
Homework Statement
This is just a general case I'm having trouble trying to imagine:
https://lh3.googleusercontent.com/-mTyOwzfLy0E/VluaNlxEddI/AAAAAAAAAEk/2Creguw3xzY/w530-h174-p-rw/Screenshot%2Bfrom%2B2015-11-29%2B21%253A34%253A50.png
Suppose there is a cylinder, kind of like a yo-yo, that...
Let's ignore gravity in this problem for simplicity. For a wheel rolling without slipping on some surface, the rest point is the point at a given instant of time that is in contact with the surface (the rest point has zero instantaneous velocity). If the wheel is rolling at constant velocity...
A clown balances a small, spherical grape at the top of his bald head, which also has the shape of a sphere. After drawing sufficient applause, the grape starts from rest and rolls down without slipping. It will leave contact with the clown's head when the radial line joining it to the curvature...
For conditions where an object is rolling without slipping on a rough, flat surface, the object posses a net torque about the center of mass provided by friction at the contact point. Hence, why doesn't the object accelerate radially indefinitely?
For ex, if we had a slippery bowling ball...
If there is a uniform ball rolling without slipping on an inclined plane, does gravity provide a torque, translational force, or both? I'm just really confused about forces vs. torques i guess?
Homework Statement
A marble that is rolling without slipping approaches a hill at 8.5 m/s. How high vertically will the marble go under these circumstances:
If the hill is rough enough to prevent any slipping?
If the hill is perfectly smooth?
Why does the marble rise to different heights when...
Homework Statement
A hollow, spherical shell with mass 1.85kg rolls without slipping down a slope angled at 32.0∘. Find the acceleration, friction force, and coefficient of friction.
Homework Equations
atan= rα
τ=rFsinΘ
I=matan
The Attempt at a Solution
I'm not quite sure where to begin. I...
Homework Statement
A hollow spherical shell with mass 2.50kg rolls without slipping down a slope that makes an angle of 33.0 with the horizontal.
Find the minimum coefficient of friction μ needed to prevent the spherical shell from slipping as it rolls down the slope.
Homework EquationsThe...
Homework Statement
Do the equations below only apply for rolling without slipping?
Homework Equations
vcm=rw, a=(gsintheta)/(1+I/(MR)^2)
cm=center of mass
3. The Attempt at a Solution [/B]
I know that they both apply for rolling without slipping, but do they apply when there is slipping...
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.
Homework Equations
F=ma, torque=I(alpha)...
Hi,
Please note: this is not a homework assignment. It is taken from an exam and I'd appreciae some clarifications.
In the setup delineated in the attachment, a small cylinder of mass M and radius R rolls without slipping inside a larger cylinder of radius 10R. It is stated that the larger...
Hello PF!
Homework Statement
A string is wrapped around the small cylinder as shown. You pull with a force F (and the cylinder does not slide). Calculate the acceleration of the cylinder CM (including direction). Here r = 3 cm,
R = 5 cm, F = 0.1 N, and m = 1kg. [Make sure to define one...
This is the second part of a 2 part problem. The first part is:
A solid disc is rolling down a 30 degree incline from rest.
a. draw the force diagram for the disk.
b. write the equations for both translation and rotational motion
c. Find the linear acceleration of the center of mass.
d...
Hi,
The below questions are NOT HW questions, but I have a big exam coming and I would wholeheartedly appreciate some/any assistance with the following two issues, namely:
(1) Direction of static friction in case of rolloing without slipping
(2) Direction of α and VCM in case of rolling without...
I've been having trouble with this topic for a while now. I've re-read the section dozens of times now, but I'm still not exactly clear and I was hoping for clarification on a couple of things.
In a system of particles, I can see intuitively how the velocity of a particular particle will be the...
Homework Statement
Homework Equations
Angular momentum/fixed axis rotation
The Attempt at a Solution
Hi guys. I'm having a bit of trouble visualizing what will happen so if you could first indulge me with the mechanics. Imagine there was no friction to begin with; since the force...
In rolling without slipping, why does the point of contact have zero velocity relative to the ground? If so, how can the point of contact move relatively to the ground? (It has to move relative to the ground, otherwise it cannot roll and must stay in its original position)