Rotational motion Definition and 600 Threads

I've also attached the picture of this problem at the end of the post. A uniform rod of mass 4:5 kg is 10mlong. The rod is pivoted about a horizontal, frictionless pin at the end of a thin extension (of negligible mass) a distance 10 m from the center of mass of the rod. Initially the rod...

the quantity of rotational motion that plays same role as that of mass in linear motion is _____________---

Every rotational motion have torque? Pls come and take a look.. Are torque exsiting at every rotational motion? how about free fall or wheel rotating without any force act on it?? Question: A 0.8m diameter, 50kg flywheel with a radius of gyration of 0.283m must be braked from 60 rpm to...

1. I need some ideas on how to demonstrate angular velocity and angular acceleration in the class. 3. We have some wheels w/ handles on either side that we can use to show rotation. We're going to apply the equations of angular velocity and acceleration to that. Does anyone have any...

Homework Statement A digital audio compact disc carries data, with each bit occupying 0.6 (mu)m, along a continuous spiral track from the inner circumference of the disc to the outside edge. A CD player turns the disc to carry the track counterclockwise above a lens at a constant speed of 1.3...

One end of a meter stick is pinned to a table, so the stick can rotate freely in a plane parallel to the tabletop. Two forces, both parallel to the tabletop, are applied to the stick in such a way that the net torque is zero. One force has a magnitude of 1.90 N and is applied perpendicular to...

Homework Statement A wheel decellerates from 100 rpm in 10 sec. Find angular acceleration, torque and the force torque is producing on a fixed object. The wheel has a radius of .0025m and a mass of 50kg. Homework Equations T=Ia a=ra T=dL/dt The Attempt at a Solution The first...

Homework Statement A stuntman whose mass is 70 kg swings from the end of a 4.0-m-long rope along the arc of a vertical circle. Assuming he starts from rest when the rope is horizontal, find the tensions on the rope that are required to make him follow his circular path,(a) at the beginning of...

Hey everyone, first time poster here:smile: It's a really great forum though! I can't seem to figure out this problem. If anyone could help that would be great. 1.A bicycle has wheels with a diameter of 0.650 m. It accelerates uniformly and the rate of rotation of its wheels increases...

1. A uniform stick of mass m and length l spins arounds on a frictionless horizontal table, with its CM stationary (but not fixed by a pivot). A mass M is placed on the plane, and the end of the stick collides elastically with it, as shown. What should M be so that after the collision the...

Hi. I did a 5 part problem and I just want to know if I did it right or if I'm on the right track. Please help. Thank you. The problem is as follows: Two identical grinding wheels of mass m and radius r are initially spinning about their centers. Wheel A has an intial angular speed of w...

A cylinder is observed to be rolling freely at a constant speed on a horizontal surface. Which of the following statements is true? a.It is possible that the cylinder is both rolling and sliding at the same time, i.e. that v, the speed of the centerpoint, is not = to rw. b.If the cylinder...

Ok the problem is: Energy is to be stored in a flywheel in the shape of a uniform solid disk with a radius of 1.30 m and a mass of 72.0 kg. To prevent structural failure of the flywheel, the maximum allowed radial acceleration of a point on its rim is 3600 m/s^2. What I did was solve for...

It looks like your standard matchbox car loop. I need to find the minimum height h that will allow a solid cylinder of mass m and radius r_1 to loop the loop of radius r_2. "Express h in terms of the radius r_2 of the loop." I am not quite getting a certain portion of this. I know the...

"Consider the bicycle wheel is not turning initially. A block of mass m is attached (with a massless string) to a wheel. The block is allowed to fall a distance of h. Assume that the wheel has a moment of inertia I about its rotation axis. Find the angular speed of the wheel after the block...

These problems have diagrams with them so I posted those pictures are at http://viewmorepics.myspace.com/index.cfm?fuseaction=viewImage&friendID=21023924&imageID=1420239256 1) A spherical ball rolls up an incline. Determine the acceleration of the ball and the magnitude and direction of...

Hi, I'm really confused about these 2 problems to the extent that I have no idea where to start. Any kind of suggestions and hints would be really appreciated. Thanks A 1090-N uniform beam is attached to a vertical wall at one end and is supported by a cable at the other end. A...

One more problem on a tough worksheet...I have tried it for a while, but can't find an equation(s) suitable for the problem... A constant force of 12N is applied to the axle of a disc rolling along a flat plane. The disc has mass m=22kg, diameter D=.50m, and rotational inertia I=.688kgm^2...

This question really has me stumped. Am I right to just ignore the fact that there is an inner control room ring? This is what I think I will need: We haven't gotten to inertia yet, but I think this is an inertia problem. I = MR^2 (if I take out the inner ring and say it is a thin-walled...

I'm having trouble with these two "classic meter stick problems" 1: A rod of length L and mass M stands vertically on a flat frictionless surface. A wad of putty of mass m and initial velocity v strikes the stick at a right angle at height 3/4 L. The collision is perfectly inelastic. Find the...

Why is it that when you spin a piece of plastic bent slightly upwards on a flat surface, it spins normally for a little while, slows down, and then spins the other way for a bit before stopping? My professor did a demo of this in class and didn't really explain it.

The Sun subtends an angle of about 0.5 degrees to us on the Earth, 150 million km away. What is the radius of the Sun? theta=l/R (2pi rad/360 degrees)0.5 degrees=2pi(150,000,000 km) This should be simple, but the answer I get seems to not sound right at all Have i set this up correctly?

Rotational Motion on an Axis Problem: Helpppp? Problem: Two thin rectangular sheets (0.20 m x 0.40 m) are identical. In the first sheet the axis of rotation lies along the 0.20-m side, and in the second it lies along the 0.40-m side. The same torque is applied to each sheet. The first sheet...

Ok, here's a problem on a quiz that i just can't figure out. I'm having trouble drawing it in the first place: ----------- At the moment before a diver jumps from a diving board, a force of 1.200 X 10^3 N is exerted on teh diver at an angle of 90 degrees to the board. This force produces a...

A 32.0 kg wheel, essentially a thin hoop with radius 1.20 m is rotating at 280 rev/min. It must be brought to a stop in 15.0s (a) How much work must be done to stop it? t=15.0s m=32.0kg r=1.20m ω= 29.3 rad/s after conversion I need to find W I think I need to find torque in order to find...

hey guys, jus wunna see how u solve this question. -a car traveling on a flat(unbanked) circular track accelerates uniformly from rest with a tangetial acceleration of 1.70m/s(squared). the car makes it one fourth of the way around the circle before it skids off the track. cetermine the...

Hey guys i have only one question this time on my homework :cool: 1) At t=0 a grinding wheel has an angular velocity of 28.0 rad/s. It has a constant angular acceleration of 29.0 rad/s^2 until a circuit breaker trips at time t=2.50s. From then on, it turns through an angle 433rad as it...

Hey everyone, Okay, so I'm just not sure how to solve this problem exactly and could use some kind advice. A heavy ball is connected on the end of a light rope and undergoing rotation witha radius of X, let's say. At t= 19.3s a=10.2m/s^2. At t=7.4s what was the acceleration. How does...

Any ideas on how to approach / set up the following problem? http://img124.imageshack.us/img124/9707/untitled8vv.jpg

The tires of a car make 85 revolutions as the car reduces its speed uniformly from 90 km/h to 30 km/h. The tires have a diameter of 0.80 m. (a) What was the angular acceleration of the tires? rad/s2 angular acceleration = Omega final- Omega intial / Delta Time does that mean that in...

the question is about that: Ayo-yo is made from two uniform disks, each with mass m and radius R, connected by a light axle of radius b. A light, thin string is wound several times around the axle and then held stationary while the yo-yo is released from rest, dropping as the string unwinds...

I figured out the first part of the problem below, but I haven't been able to solve the second part. http://img148.imageshack.us/img148/2097/untitled13jb.png http://img89.imageshack.us/img89/5061/untitled6ez.png What I have so far: I solved for angular acceleration with alpha = v...

Thanks in advance for the help. Here are the problems: A uniform rod is free to rotate about a frictionless pivot at one end. The rod is released from rest in the horizontal position. What is the magnitude of the angular acceleration of the rod at the instant it is 60 degrees below the...

A uniform 2.9-kg cylinder can rotate about an axis through its center at O. The forces applied are: F1 = 2.4 N, F2 = 3.9 N, F3 = 6.1 N, and F4 = 4.6 N. Also, R1 = 11.2 cm and R3 = 4.0 cm. Find the magnitude and direction (+: counterclockwise; -: clockwise) of the angular acceleration of the...

A small spherical ball of radius r = 1.5 cm rolls without slipping down a ramp and around a loop-the-loop of radius R = 2.6 m. The ball has mass M = 358 g. How high above the top of the loop must it be released in order that the ball just makes it around the loop? --- i just calculated the...

This is the doubt that troubled me when the chapter of rotational motion started. If torque is applied on a body for sometime and then the torque is stopped, then will the body continue to rotate for ever? Yes - coz the rotational Kinetic energy Iw^2 must be conserved since no mommentum is...

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 been moved part way...

Some times it becomes very difficult to differenciate between Circular motion and Rotational motion.Can anyone tell me to understand clearcut diff. between the two?

The drawing shows the top view of two doors. The doors are uniform and identical. Door A rotates about an axis through its left edge, and door B rotates about an axis through the center. The same force is applied perpendicular to each door at its right edge, and the force remains perpendicular...

Hint: Consider the wheel's energy. Consider a wheel of radius 1.23 m, mass 7.7 kg and moment of inertia I =1/2 MR^2 (it's a solid disk). The wheel rolls without slipping in a straight line in an uphill direction 30 degrees above the horizontal. The wheel starts at angular speed 16.1 rad/s...

Hello, If anyone out there could help me with this problem it would be much appreciated. The problem is on rotational motion and it states: A proposed space station includes living quarters in a circular ring 52.0 m in diameter. At what angular speed should the ring rotate so the occupants...

Question: "A uniform rod of mass m and length 2a stands vertically on a rough horizontal floor and is allowed to fall. Assuming that slipping has no occured, write the angular velocity of the rod as a function of the angle Theta the rod makes with the vertical." WORK DONE: Ic = (ml^2)/3...

:confused: 1.) A uniform rod of mass 0.93 kg is 17 m long. The rod is pivoted about a horizontal, fric- tionless pin at the end of a thin extension (of negligible mass) a distance 17 m from the cen- ter of mass of the rod. Initially the rod makes an angle of 70 degrees with the...

Hey all, thought I should ask about a couple problems... 1 - A rotating door is made from four rectangular glass panes, as shown in the drawing. The mass of each pane is 95 kg. A person pushes on the outer edge of one pane with a force of F = 80 N that is directed perpendicular to the pane...

1) A .65 kg on the end of thin light rod is rotated in a horizontial circle of a radius 1.2 m. (a) Calculate the moment of inertia of the ball about the center of the circle, and (b) the torgue needed to keep the ball rotating at constant angular velocity if air resistence exerts a force of .020...

A spool of thin wire rotates without friction about its axis. A man pulls down on a wire connected to an inner radius with force of 16.3 N. How long does it take to increase the angular velocity of the spool from 15.0 rad/s to 33.0 rad/s? Icm = 0.550 kgm2 Inner radius, r = 0.300 m Outer radius...

I don't know if I'm suppose to put this in this forum because it's for 1st year university physicz..wasn't sure if it was intro or not but anyways...I need some help doing the following questions... 1.A wheel (like one of those wooden ones like they had in the oldern days) has 8 equally...

I have a few Rotational Motion and Equilibrium problems that I hav been working on but I am not sure if I completed them correctly. I will show what I have done so far and if anyone could point me in the right direction I would appreciate it. Please, numerical explanations are easier for me to...

"A string is wound around a solid cylindrical spool of mass 9.4 kg and radius .11 m. Assume the acceleration of gravity to be 9.8 m/s^2. If the spool is released from rest and rolls along the string and the distance to the floor is 9.06 meters, then how long in seconds will it take the spool...

A solid cylinder, a solid sphere, and a hoop all of the same mass but different radii, roll without sliding down an inclined plane. The body that gets to the bottom first will invariably be: the cylinder the sphere they all arrive together not enough information the hoop...