Rolling Definition and 1000 Threads

Homework Statement The dropped disk rolls down with acceleration of centre of mass. The disks are identical, find accleartion of cm in terms of angular acceleration Homework Equations [/B] a = r*alphaThe Attempt at a Solution I don't know where to begin, I think the alphas should be equal...

Homework Statement Homework EquationsThe Attempt at a Solution Since the wheel is rolling , vcm=ωr , acm = αr The wheel is in pure rotation about the point O where it touches the surface . The point P is a distance 4/3 from the bottom point . Angular acceleration of the point = 3 rad/s2...

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 sphere of mass m2 and radius R rolls down a perfectly rough wedge of mass m1. The wedge sits on a frictionless surface so as the sphere rolls down, the wedge moves in opposite direction. Obtain the Lagrangian. Homework EquationsThe Attempt at a Solution Here's my diagram...

I have to be missing something very obvious in this. Homework Statement A car travels 80km/h on a level road in the positive direction of an x axis. Each tire has a diameter of 66 cm. Relative to a person riding in the car, what is the velocity of a) center, b)top, and c) bottom of the tire...

Let's say we have a rolling without slipping (e.g. mentioned ball) on flat surface. Does it mean that the ball will accelerate to infinity ?

hello, Could you please help me to understand how this steel ingot rolling system works. The simplified diagram of a rolling mill is shown in the figure attached. The upper roller of mass m is driven by an electro-hydraulic actuator his objectif is to adjust the thickness to be given to the...

Homework Statement A point mass m is fixed inside a hollow cylinder of radius R, mass M and moment of inertia I = MR^2. The cylinder rolls without slipping i) express the position (x2, y2) of the point mass in terms of the cylinders centre x. Choose x = 0 to be when the point mass is at the...

Hey, everyone, I have a question regarding quadcopters, when the set of the arms is of configuration X, to roll we increase the velocity of the two motors on the left/right and decrease the other motors on right/left, the question is when doing so the total angular velocity is zero that means...

Homework Statement Homework EquationsThe Attempt at a Solution In rolling motion, friction doesn't work. So, applying work energy theorem, ## \frac 1 2 m v_0 ^2 =\frac 1 2 mv^2 + \frac 1 2 I_{center} \omega ^2 ## ## taking~ I_{ center} = \frac 2 5 m R^2 ~and ~ v =\omega R , v = \sqrt {(...

Homework Statement A cylinder is placed on bars.The separation of each bar is l.The cylinder is then pulled with a force F through its center.Find the terminal velocity of the object.Assume l<<R and the ball rolls without slipping. Homework Equations 1/2 mv^2 +1/2 Iω^2 = kinetic energy Work is...

Homework Statement In the picture ,problem 8.29 Homework Equations Energy conservation ,velocity relation ,momentum The Attempt at a Solution First i defined the speed of the body relative to the ground as Vb and speed of plane relative to the ground as Vp. From momentum ,VbcosΘ=-Vp .From the...

Homework Statement A coin of radius R rolls around a coin of radius 3R which is fixed.If the coin rolls without slipping, How many times does the coin rotates around its axis ? Homework Equations Xpm=RΘ for non slipping The Attempt at a Solution The center of mass moves a distance of...

Homework Statement A cylinder of mass M and radius R rolls without slipping on a plank that is accelerated at rate A. Find the acceleration of the cylinder. Homework EquationsThe Attempt at a Solution Physical force acting on the system : Fphy = N + mg + fr w.r.t. plank frame i.e non -...

I have been reading quite a lot about the Physics behind car dynamics and I have gotten to a point which keeps confusing me, namely - brake locking. I understand brake locking as the situation when the wheels of the car do not rotate anymore but the car is still moving - this causes the tires...

This post is about the methodology required to produce the Fig. 9 Part C “optical appearance” plot as calculated by Øyvind Grøn in "Space geometry in rotating reference frames: A historical appraisal". http://areeweb.polito.it/ricerca/relgrav/solciclos/gron_d.pdf In 2014 I contributed to a...

Homework Statement Side by side on the top of an incline plan with height=2 meters a cylinder (Ic= MR^2/2) and a sphere (Ie=2MR^2/5) with equal radius, that come down to the base, rolling without slipping. Mass of the cylinder = 2.0 kg; Mass of a sphere=4.0 kg. Homework Equations $$K_r= 1/2...

Homework Statement A solid sphere of radius 16cm and mass 10kg starts from rest and rolls without slipping a distance of 9m down a house roof that is inclined at 43 degrees. What is the angular speed about its center as it leaves the house roof? The height of the outside wall of the house is...

So I know that given a unchanging hill, and same mass between a sphere and cube, that the cube should slide down the hill faster (assuming negligible friction). This is observed through the energy "lost" by the sphere which instead of having all of its potential energy transferred towards...

Homework Statement An extra-curricular theoretical assignment I have received: A car is traveling on a completely flat/uniform straight road at a constant velocity on a clear, dry day. 100 meters ahead, underneath the road there is a roller (similar to a rolling-road) which can spin without...

Homework Statement [/B] A wheel, of radius 200mm, rolls over the top of a hill with a speed of 20m/s and negligible friction losses. (I = 1/2mr^2) Homework Equations [/B] Find the speed of the wheel when it is 10m below the top. The Attempt at a Solution [/B] mgh = 1/2mv^2 + 1/2IW^2 W=...

Hello. The following situation I thought out confuses me so I am wondering where my mistake lies. A uniform disk of mass M and radius R sits on its edge. A string is attached to the highest point and pulled with a Force F in the x direction. The moment of inertia of the disk is MR^2/2 making...

Hi there, I noticed that when I release the cap it moves forward slightly (away from me) which I attribute to the surface being not level and my hand applying a small force. However, the cap will roll backwards afterwards (towards me). What is causing the cap to roll back and forth? It...

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 An 7.80-cm-diameter, 400 g solid sphere is released from rest at the top of a 1.70-m-long, 20.0 degree incline. It rolls, without slipping, to the bottom Homework Equations I=2/5 Mr^2 K = 1/2 m*v^2 Kroll = 1/2 Iw2 mgh=K+Kroll The Attempt at a Solution Using the above energy...

[Mod note: Thread moved from General Discussion forum, so no homework template is shown] So - I've no idea where to write this but... I was looking at this post : https://www.physicsforums.com/threads/car-rolling-down-a-hill.302812/ And started to answer it as it was similar to some stuff...

Homework Statement Two solid spheres one of mass 'm' and other of mass '2m' are comin towards each other(translationally) with a velocity v1 and v2.After collision the sphere of mass 2m comes to rest and the sphere of mass m does oblique projectile motion at an angle 30 with the vertical till...

Hi there! I chanced upon this problem whilst trying to brush up my Classical Mech knowledge and found it confusing. Hope someone out there can provide an insight! Homework Statement A bowling ball of mass m and radius R sits on the smooth floor of a subway car. If the car has a horizontal...

Homework Statement Two identical cylinders are released from the top of two identical inclined planes. If one rolls without slipping and the other slips without rolling then which one will reach the bottom first? How will their speeds compare when they reach bottom of incline? I am not sure if...

Hi, I need to choose a hydraulic hub motor for a vehicle which weighs 25 000 N when fully loaded. The vehicle must be able to start moving (fully loaded) on a inclined surface (30 degrees angle). So I need to determine the torque needed to get vehicle moving. The vehicle has three wheels from...

Consider a sphere constrained to roll on a rough FLAT HORIZONTAL surface. A book on classical mechanics says it requires 5 generalized co-ordinates to specify sphere's configuration: 2 for its centre of mass and 3 for its orientation. I did not understand why 3 for orientation. I guess only 2...

Homework Statement A uniform ring of mass m and radius r is projected horizontally with velocity v on a rough horizontal floor,so that it starts off with a pure sliding motion and it acquires a pure rolling motion after moving a distance d.If the coeffcient of friction between ground and ring...

Homework Statement Homework EquationsThe Attempt at a Solution This is the problem in Goldstein's classical mechanics exercise 1.11 I wonder why the solution doesn't consider rotational kinetic energy (1/2 I w^2) So, L= T = 1/2mx^2 + 1/2 I w^2 .

Greeting fellow physicists, I have been having some questions from my AP Physics C: Mechanics students about the direction of friction in rolling. Here are a few situations. 1. For a wheel that is accelerating to the right while rolling smoothly, it must also be rotating clockwise. In order to...

Homework Statement [/B] A uniform cylinder with radius r is rolling down an incline without slipping as shown in diagram below. It's angular acceleration is α and acceleration of it's center of mass C is a. What will be the linear acceleration of point of contact P and another point Q on the...

Hello, this is my first time on this site as a member, but I have found it very helpful all year. In my physics class we are trying to come up with a way to get a can to roll down an incline as fast as possible. We have to empty out the food from the can, then do whatever we can to it to make it...

I don't know how to analyze data proper-like. What variance would be considered statistically significant, such that one might conclude a die is not fair? I just rolled a six-sided die 192 times. There are my results: 32, 28, 35, 37, 29, 31. So, they vary from average by 0, -4, +3, +5, -3...

Hi, I need some help to verify whether this is possible or not. I am working on a project that still in early phase of development. The idea is to create a water filter system to in a barrel as rolling it. Basically the barrel will contain 4 panels placed inside the barrel creating a shape of...

Ok...Suppose I try to roll a ball to the right...Its surface at the point of contact with the floor would be deformed, which would cause some ''rolling friction'' to the left, which in turn would cause some clockwise torque(rolling motion) in the ball...(please point out if something is wrong in...

Homework Statement A ball of mass m is given an initial velocity ⃗v and entered into a funnel. Model the acceleration of the ball over a period of time. Note: I don't have a full problem statement because this isn't really a homework question (but I figured it was homework-like enough to post...

Homework Statement A cart with mass M has four wheels (idealized as uniform discs), each of radius r and mass m, arranged symmetrically with respect to the cart. Find the acceleration of the cart when a horizontal force F is applied on it. There is no slipping between the wheels and the...

Both the questions are at https://imgur.com/a/o7B20 The problem I am facing is that on a straight line friction is there and I can't balance it. Using F=ma and T=Iw doesn't work.

Homework Statement Please see the attached In this example my professor is trying to calculate the total KE of the hoop,and let since the velocity at the contact point of the hoop and tube is zero we have v = vt + aω.This is equivalent to (R-a)Θ. = - aω. However,he later said that it was...

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...

A cylinder rolls on a horizontal, flat surface without sliding towards the left, so it must be rolling anticlockwise about its center of mass (CM). Suppose it slows down to a stop due to friction. What is the direction of the friction at the point of contact? Since it slows down, friction must...

(This is NOT a homework problem. It's an engineering problem I'm trying to crack.) A wheel with a rubber tire (friction) can roll on a suspended rail. Attached to it is a pendulum that's rigidly mounted on the axle of the wheel with a mass that can hand down and swing. (The wheel's rotation...

Homework Statement With the equations of motion in polar coordinates given by ##r(t)=pcos{kt^2}, φ(t)=kt^2## determine the velocity intensity of a point ##M## on the circumference of a cylinder which is rolling without friction on a horizontal plane at time ##t## is the velocity of the center...

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...

Say a ball rolls down to the right with slipping with on an arc incline so that at the bottom it leaves horizontally. The instant it leaves horizontally and is now on a cart with mass with frictional surface. So the ball will roll on the cart with kinetic friction pushing to the left altering...