Rotational motion Definition and 614 Threads

Homework Statement A ring of mass M is hung from the ceiling. At the top of the ring are two smaller rings of mass m. There is no friction between the big and small rings. If two smaller rings slip down the big ring, for what value of m will the big ring move upward. A picture is attached to...

1.A centrifuge rotor rotating at 5000 rpm is shut off and is eventually brought uniformly to rest by a frictional torque of 1.60 m·N. If the mass of the rotor is 4.70 kg and it can be approximated as a solid cylinder of radius 0.0780 m, through how many revolutions will the rotor turn before...

Homework Statement Two cars race around a circular track. Car A accelerates at 0.340 rad/s2 around the track, and car B at 0.270 rad/s2. They start at the same place on the track and car A let's the slower-to-accelerate car B start first. Car B starts at time t = 0. When car A starts, car...

I ran across this problem studying for my exam, and I'm not sure how to solve it: Homework Statement A thin rod of Mass M and length L is supported by a pivot a distance of L/4 from its left end. A second support a distance 3L/4 from the left end prevents it from falling. A clay ball of...

I was absent from school for 3 days and my teacher gave this worksheet to me. I have no idea what I'm doing on it. Can anyone please help me with this? Thanks.

Suppose a man is holding his arms extended in with some masses in each hand. He is set rotating about a vertical axis . If he pulls his hands toward his stomach then according to law of conservation of angular momentum there is an increase in his angular velocity. Also there is a change in his...

Rotational Motion Find g - Galileo Inclined Plane Homework Statement Galileo measured the acceleration of gravity by rolling a sphere down an inclined plane. Suppose that, starting from rest, a sphere takes 1.6s to roll a distance distance of 3.00 m down a 20 degree inclined plane. What value...

Homework Statement A solid cylinder of weight 50 lb and radius 3.0 inches has a light thin tape wound around it. The tap passes over a light smooth fixed pulley to a 10 lb body hanging vertically in the air. If the plane on which the cylinder moves is inclined 30 degrees to the horizontal...

Homework Statement A square plate is tilted on one of its corners as shown below. If the corner does not slip, and the plate is allowed to fall, determine the velocity of the moving corner before it hits the ground. The moving corner is point P, which is 45 degrees above the horizontal...

Homework Statement A 919 kg rollercoaster is about to go up a hill that acts as the top of a circle 16.21m in diameter. What is the fastest that car can move (in m/s) without leaving a track? known: mass: 919 kg diameter: 16.21 radius: 8.105 Homework Equations Vt=r\omega...

A torque of 1 N.m is applied to a bike wheel of radius 35 cm and mass 0.75 kg. Treating the wheel as a hoop (I=MR^2) A. What is it's angular acceleration? Answer - 10.9 rad/s^2 B. If the wheel starts from rest, what is its angular speed after 5 seconds? Answer - 54.4 rad/s C. How many turns...

Homework Statement consider a yo-yo with R = 3.3 cm, r = 0.3 cm, and mass m = 84 g. What is the speed of the yo-yo after it has fallen a distance h = 1.20 m? What is the tension in the string while the yo-yo falls? What is the magnitude of the acceleration of the centre of mass as the...

Homework Statement A skater spins with an angular speed of 8.3 rad/s with her arms outstretched. She lowers her arms, decreasing her moment of inertia by a factor of 8.9. Ignoring the friction on the skates, determine the percent of change in her kinetic energy. Answer in percent...

Homework Statement A turntable that is initially at rest is set in motion with a constant angular acceleration α. What is the magnitude of the angular ve- locity of the turntable after it has made one complete revolution? Homework Equations w(omega)^2 = w(omegeInitial)^2 +2α(delta)θ...

Homework Statement An inextensible light string of length 2 m is fixed at one end A and carries at its other end B a particle of mass 3 kg, which is rotating in a horizontal circle whose centre is 1 m vertically below A. Find the angular velocity of the particle and the tension in the...

This is merely a simple, but conceptual, problem. Say we have a cue ball of mass M and Radius R rolling without slipping on the pool table. What is the the meaning of the ∫v(t)dt - ∫Rw(t)dt where w(t) is the angular speed of the pool ball. My guess is that this represents the length the ball...

Homework Statement A narrow but solid spool of thread has radius R and mass M. If you pull up on the thread so that the CM of the spool remains suspended in the air at the same place as it unwinds, (a) what force must you exert on the thread? (B) how much work have you done by the time the...

Homework Statement A wheel of radius 0.358 m is mounted on a frictionless horizontal axis. The rotational inertia of the wheel about the axis is 0.0421 kg·m2. A massless cord wrapped around the wheel is attached to a 3.21 kg block that slides on a horizontal frictionless surface. If a...

Homework Statement Consider a ball of mass m on the end of a string of length l. It hangs from a frictionless pivot. The ball is pulled out so that the string makes an angle thetai with the vertical and is then released. a. Find w (angular velocity) as a function of the angle the strings...

Homework Statement A wheel has a radius of 0.40 m and is mounted on frictionless bearings. A block is suspended from a rope that is wound on the wheel and attached to it. The wheel is released from rest and the block descends 1.5 m in 2.00 s while the wheel rotates clockwise. The tension in...

Having a problem figuring this out; it appears extremely easy but I would understand if rotational motion comes into play. I'm just not sure where. A cylinder of mass 2kg is rolled up an incline by means of a string arranged as shown in the figure. (incline with angle theta and a cylinder...

Solid cube of side 2a and mass M is sliding on a frictionless table with velocity v. It hits a small obstacle at the end of the table causing it to tilt. What is the minimum velocity to cause the cube to fall off the table? Totally no clue where to start I don't even know what's the condition...

Note: I refrained from using any of the latex references, so bear with me. Homework Statement A rubber ball with a radius of 3.2 cm rolls along the horizontal surface of a table with a constant linear speed v. When the ball rolls off the edge of the table, it falls 0.66 m to the floor below...

Homework Statement A high school buddy exerts a horizontal force on a swing that is suspended by a rope that is 5.0 meters long, holding at an angle of 30 degrees with the vertical. The child in the swing has a mass of 30kg and dimensions that are negligible compared to the length of the...

Homework Statement A shaft is turning at 73.8 rad/s at time zero. Thereafter, its angular acceleration is given by a = -10.1 rad/s2 - 4.44 t rad/s3. where t is the elapsed time. Calculate its angular speed at t = 2.58 s Homework Equations 1/2(Angular accel formula)+ 73.8t+0= theta...

Homework Statement A car is designed to get its energy from a rotating flywheel with a radius of 1.85 m and a mass of 678 kg. Before a trip, the flywheel is attached to an electric motor, which brings the flywheel's rotational speed up to 3610 rev/min. Find the kinetic energy stored in the...

Homework Statement An electric motor can accelerate a Ferris wheel of moment of inertia 19200kgm2 from rest to 9.11 rev/min in 10.7s. When the motor is turned off, friction causes the wheel to slow down from 9.11 rev/min to 7.36 rev/min in 9.55s. Determine the torque generated by the motor to...

1. Mass m_1 on the frictionless table of the figure is connected by a string through a hole in the table to a hanging mass m_2. With what speed must m_1 rotate in a circle of radius r if m_2 is to remain hanging at rest...

A block of mass 2kg and 6kg are connected by a massless string over a pulley in the shape of a solid disk having radius R=0.25m and mass 10kg.These blocks are allowed to move on a fixed wedge of angle 30\circ the coefficient of kinetic friction block is 0.36. Find the acceleration of the blocks...

Imagine a trebuchet with a stiff rod of 3m and neligible mass.Two masses 60kg and 0.12kg are at its end with the bigger mass 0.14m away from the pivot point. Find the maximum speed the smaller mass attain. Alright the question is somewhat like this and i start of by finding the moment of...

Homework Statement A thin rod of mass M and length L rests on a frictionless table and is struck L/4 from its CM by a clay ball of mass m moving at speed v. The ball sticks to the rod. Determine the translational and rotational motion. Homework Equations Irod=1/12*M*R^2 I=mR^2 L=Iw or L=r*m*v...

ok I am not sure what this kind of motion is called but it is caused when a cylinder, a AA battery let's say, is liying on a flat smooth surface and a torque is applied to one end which causes the battery to stand up and spin on one of its ends. I've been looking for a name or a few details...

Here are a couple of questions I'm having trouble with. 1) Can a magnet have 3 poles? [Note: I've been told that a magnet might develop two north poles at the centre and two south poles at either end if it is faultily magnetised, but I'd much appreciate some explanation=)] 2) If the...

Homework Statement Two objects of equal mass are on a turning wheel. Mass 1 is located at the rim of the wheel while mass 2 is located halfway between the rim and the axis of rotation. The wheel is rotating with a non-zero angular acceleration. For each of the following statements select the...

Homework Statement A ball is suddenly kicked across a floor. It initial will have a linear velocity, but no initial angular velocity. The object will slide for a distance "d" until perfect rolling kicks in. all are in terms of variables and not specific numbers A.) derive an equation...

Homework Statement A car initially traveling at 25.9 m/s undergoes a constant negative acceleration of magnitude 2.10 m/s2 after its brakes are applied. (a) How many revolutions does each tire make before the car comes to a stop, assuming the car does not skid and the tires have radii of...

Homework Statement A rotating governator is designed as shown. A 8.66 lb collar at the bottom can slide freely along the shaft (no friction). Initially the collar is 2.00ft from the top. As the governor rotates, the collar is pulled upwards, and when it reaches a distance of 1.732 from the...

Homework Statement An object of mass 7.1x1023 circles the Earth and is attracted to it with a force whose magnitude is given be Gmem/r2. If the period of rotation is 32 days, what is the distance from the Earth to the object? Here G=6.67x10-11 Nm2/kg2, me=6x1024 kg. Homework Equations...

A sphere of radius a rests on top of a fixed rough circular cylinder of radius R which is lying with its principal axis horizontal. The sphere is disturbed and rolls, without any slipping, around the surface of the cylinder. Show from energy considerations that, if theta is the angle to the...

Homework Statement Neutron stars are extremely dense objects that are formed from the remnants of supernova explosions. many rotate very rapidly. suppose that the mass of a certain spherical neutron star is twice the mass of the sun and its radius is 10.0 km. determine the greatest possible...

Homework Statement A man, of m = 70 kg, walks along a thin rigid plank, of M = 210 kg. The plank sits on the roof of a 10 story building and is placed so that its center of mass sits directly on the edge of the roof. Where, along the plank, can the man move before the plank tips over the...

Homework Statement A 750 gram grinding wheel 25.0 cm in diameter is in the shape of a uniform solid disc. When it is in use it turns at a constant 220 rpm about an axis perpendicular to its face through its center. When the power is switched off the wheel stops in 45.0 s with constant angular...

Homework Statement A disk with a radial line painted on it is mounted on an axle perpendicular to it and running through its center. It is initially at rest, with the line at q0 = -90°. The disk then undergoes constant angular acceleration. After accelerating for 3.1 s, the reference line has...

This is not a traditional homework question: Anyone familiar with the the U texas homework will understand: Does anyone have the answer key to the utexas physics homework on rotational motion? Our teacher hasn't taught us anything on rotation. We are desperate to know how to do these...

Homework Statement I'm just working through a few past mechanics papers and this question came up: A belt drives the circumference of a cylindrical wheel of radius R and mass M with no slipping. The tension in the belt is T. Friction in the wheel bearing causes an effective torque N...

Homework Statement I did a lab today where a weight was tied to a string. The string was wrapped around part of the circumference of a wheel, and then the end was taped down. So, when I let go of the wheel and the weight, the force of gravity on the weight causes the wheel to turn. I have...

Homework Statement You are working on a project with NASA to launch a rocket to Mars, with the rocket blasting off from Earth when Earth and Mars are just aligned along a straight line from the sun. As a first step in doing the calculation, assume circular orbits for both planets. If Mars...

Homework Statement A baton twirler throws a spinning baton directly upward. As it goes up and returns to the twirlers hands, the baton turns through four revolutions. Ignoring air resistance and assuming that the average angular speed is 1.80 rev/s, determine the height to which the center...

Homework Statement A uniform 3.8-kg cylinder can rotate about an axis through its center at O. The forces applied are: F1 = 4.6 N, F2 = 6.2 N, F3 = 8.0 N, and F4 = 3.1 N. Also, R1 = 10.7 cm and R3 = 5.8 cm. Find the magnitude and direction (+: counterclockwise; -: clockwise) of the angular...

Any help would be appreciated. I'm supposed to make a 20 slide project in power point to depict how angular acceleration, net torque, and moment of inertia are related to one another, as sated in Newton's Second Law of Rotational Motion. I'm supposed to describe the basic concept of the Law and...