Angular acceleration Definition and 552 Threads

1. The tub of a washer goes into its spin-dry cycle, starting from rest and reaching an angular speed of 2.2 revolutions/s in 8.4 seconds. at this point the person doing the laundry opens the lid, and a safety switch turns off the washer, the tub slows to rest in 9.5 seconds. through how many...

[SOLVED] Angular acceleration of disk For the system below, determine the tension in each rope, the linear acceleration of each mass and the angular acceleration of the disk. \ g=10 m/s^2. Use \ I=4 kgm^2. So far I have drawn the free-body diagram for m1 and m2 \ 120 - T_1 = 12a_1 and \...

A 5.0 kg, 60-cm-diameter disk rotates on an axle passing through one edge. The axle is parallel to the floor. The cylinder is held with the center of mass at the same height as the axle, then released. What is the cylinder's initial angular acceleration? ok so this is what i think i...

Homework Statement A uniform rod of length L and mass m is supported as shown in the figure. A vertical cable at A suddenly breaks. Determine at this instant the angular acceleration of the rod and the tension in cables AE and BF. Homework Equations mass moment of intertia of bar...

I was just wondering what the equation for average angular acceleration is At first i thought it was W avg = Delta Pheta/ Delta Time but then i think that might be the Average Angular Speed formula... Any ideas? i know it's a simple question so hopefully no one will get annoyed =P

Homework Statement A person is riding a bicycle, and its wheels have an angular velocity of +20.0 rad/s. Then, the brakes are applied and the bike is brought to a uniform stop. During braking, the angular displacement of each wheel is +10.0 revolutions. (a) How much time does it...

Homework Statement A bowler throws a bowling ball of radius R = 11 cm down a lane. The ball slides on the lane, with initial speed vcm,0 = 6.0 m/s and initial angular speed 0 = 0. The coefficient of kinetic friction between the ball and the lane is 0.34. The kinetic frictional force fk acting...

Homework Statement Given a frictionless pulley system with the pulley having a mass 1/3M and radius R, and two weights of mass M and 4M attached to a light, frictionless rope on either side of the pulley: 1) Find the acceleration of the blocks 2) Find the angular acceleration of the...

A small rubber wheel is used to drive a large pottery wheel. The two wheels are mounted so that their circular edges touch. The small wheel has a radius of 2.0 cm and accelerates at the rate of 7.2 rad/s^2, and it is in contact with the pottery wheel (radius 21.0 cm) without slipping...

Derive the expression \alpha=\frac{mgr}{I+mr^{2}}for the acceleration a=\alphar of the falling mass m I don't even know what this question is asking... Any ideas on how to approach this wonderful little puzzle?

A)If it took 0.480 s for the drive to make its second complete revolution, how long did it take to make the first complete revolution? B)What is its angular acceleration, in rad/s^2? please help

Homework Statement A solid cylinder of 24 cm radius is postioned on a frictionless plane inclined at 30 degrees above horizontal. A force F is exerted by a string wrapped around the spool. When F has a certain critical value the center of mass of the spool does not move. When this is the...

Someone actually posted this exact problem 4 months ago, but here it is. There wasn't an answer. Homework Statement Heron of Alexandria invented the steam jet engine in the first century A.D. One of his many inventions, the one shown below was invented for amusement but employs many...

Homework Statement http://img248.imageshack.us/img248/1639/cylinderjl0.jpg A uniform cylinder with a radius of R and mass M has been attached to two cords and the cords are wound around it and hung from the ceiling. The cylinder is released from rest and the cords unwind as the cylinder...

[SOLVED] Grindstone angular acceleration Homework Statement Object: a disk-shaped grindstone of mass 1.69 kg and radius 7.95 cm that operates at 707 rev/min. When the power is shut off, you time the grindstone and find it takes 32.1 s for it to stop rotating. What is the angular acceleration...

Homework Statement Starting from rest at t = 0s, a wheel undergoes a constant angular acceleration. When t = 3.9s, the angular velocity of the wheel is 6.9 rad/s. The acceleration continues until t = 19s, when the acceleration abruptly changes to 0 rad/s^2. Through what angle does the wheel...

Homework Statement A wheel is subjected to uniform angular acceleration. Initially its angular velocity is zero. During the first 1-s time interval, it rotates through an angle of 88.6degrees. (a) Through what angle does it rotate during the next 1-s time interval? (b) Through what angle...

Homework Statement State the Relatrionship between radial and angular acceleration. Homework Equations Well I presume the equations would be "radial acceleration = v(squared)/radius" The Attempt at a Solution I cannot find the equation for radial AND angular acceleration?? I...

Hey. I have been working on a relative simple 2D physics engine for a game I am making, and as I was researching the subject (rigid body mechanics) I found this article on physics in games. This pretty much answers everything. Though this is one little thing that I cannot figure out. The...

I'm trying to write a small rigid-body physics program. I already have the linear forces part done, using Euler's method. This makes it easy to take the current forces and compute the next position. The issue I'm having is that I don't know how to get the next angular position/velocity from the...

Homework Statement Info on object: Mass = 10kg Radius = 0.20m Lenght of spouts = 0.10m above surface of sphere. (The two spouts can be considered massless.) The sphere is hollow and looks like this. The pressure inside is 1.5 atm and the pressure outside is 1.0atm...

Homework Statement A person is riding a bicycle, and its wheels have an angular velocity of +19.5 rad/s. Then, the brakes are applied and the bike is brought to a uniform stop. During braking, the angular displacement of each wheel is +11.5 revolutions. (a) How much time does it take for...

Homework Statement A copper block rests 33.8 cm from the center of a turntable. The coefficient of static friction between the block and turntable is 0.52. The table starts from rest and accelerates with an angular acceleration of 0.226 rad/s². Acceleration of gravity = 9.8 m/s². After...

Homework Statement A solid cylindrical disk has a radius of 0.16 m. It is mounted to an axle that is perpendicular to the circular end of the disk at its center. When a 45 N force is applied tangentially to the disk, perpendicular to the radius, the disk acquires an angular acceleration of 110...

Homework Statement Part One: Imagine a hollow sphere of radius R and mass M. It is welded to the end of a solid rod of length L, whose mass is also M. The rod is attached to the sphere in such a way that the whole assembly, when viewed from the side, looks like a lollipop. (That is, the...

hi all, just wanted some advice on calculating a rate of deceleration of a moving vehicle, if we work out the angular acceleration of the wheel. so angular acceleration is dw/dt and is given as dw/dt=(m1-m2)/I (i.e moments of force divided by moments of Inertia) dw/dt is rad/s^2 and...

A fan blade rotates with angular velocity given by omega_z(t) = gamma - Beta(t)^2 . Calculate the angular acceleration as a function of time. I don't even know where to begin and my book is all but useless. Any ideas?

Homework Statement http://img505.imageshack.us/img505/6741/rodprobbw3.gif" Homework Equations Itot= 1/3MrL^2 + 2/5 MsR^2 + Ms(L + R)^2 = 235.69784 Cm= (Mr(L/2) + Ms(L+r))/(Mr+Ms) = 4.915 angular accel = Torque/Itot Torque= 1/2Lmgcos(theta) The Attempt at a Solution I solved for...

[b]1. 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. Determine the magnitude of the door's angular acceleration...

A pulsar is a rapidly rotating neutron star that emits radio pulses with precise synchronization, there being one such pulse for each rotation of the star. The period T of rotation is found by measuring the time between pulses. At present, the pulsar in the central region of the Crab nebula has...

Homework Statement A wheel accelerates from rest to 59 rad/s at a rate of 29 rad/s². How many revolutions the wheel turned while accelerating?Homework EquationsThe Attempt at a Solution I'm confused, I suck at this kind of problem. I got change in angular velocity which would be 59rad/s, and...

I am having a bit of trouble with the following problem. A cyclist starts from rest and pedals so that the wheels make 8.5 revolutions in the first 4.6 s. What is the angular acceleration of the wheels (assumed constant)? I multiplied 8.5 by 2pi and then divided by 4.6 sec. I get an answer...

I am having a bit of trouble with the following problem. What should I do to start? A cyclist starts from rest and pedals so that the wheels make 8.5 revolutions in the first 4.6 s. What is the angular acceleration of the wheels (assumed constant)?

i haven't been able to figure this one out... i have trouble following the explantion from my instructor. thanks for any help in advance A rigid object consists of a point mass of 2 kg momentarily located at (-3, 2) m with a force of (6, 2) N acting on it, a second point mass of 3 kg...

The problem is: The angular speed of a propellor on a boat increases with constant acceleration from 50 rev/min to 150rev/min in 2.5s.What is the angular acceleration of the propellor? I'm not sure how to go about the problem.So far I've converted the 50rev/min and the 150rev/min to...

Is this true? \vec \omega \times r = \vec v

Hi all, I am doing some homework from my textbook and I encountered this problem: "Starting from rest, a disk rotates about its central axis with constant angular acceleration. In 5.0 s, it rotates 25 rad. During that time, what are the magnitudes of (a) the angular acceleration and (b) the...

Question: A cooling fan is turned off when it is running at 850 rev/min. It turns 1500 revolutions before it comes to a stop. A. What is the fan's angular acceleration? B. How long does it take for the fan to come to a stop? I am pretty stumped with this question. I know that I have to...

Starting from rest at t = 0 s, a wheel undergoes a constant angular acceleration. When t = 1.9 s, the angular velocity of the wheel is 6.2 rad/s. The acceleration continues until t = 15 s, when the acceleration abruptly changes to 0 rad/s2. Through what angle does the wheel rotate in the...

A rotating wheel requires 2.98 s to rotate through 37.0 revolutions. Its angular speed at the end of the 2.98 s interval is 98.8 rad/s. What is the constant angular acceleration of the wheel? First I tried acceleration = (98.8rad/s - 0 rad/s) / 2.98 s - 0s = 33.15, which was incorrect...

One method of pitching a softball is called the "windmill" delivery method, in which the pitcher's arm rotates through approximately 360° in a vertical plane before the 198 gram ball is released at the lowest point of the circular motion. An experienced pitcher can throw a ball with a speed of...

A small rubber wheel is used to drive a large pottery wheel, and they are mounted so that their circular edges touch. The small wheel has a radius of 2.0cm and accelerates at the rate of 7.2rad/s^2 and it is in contact with the pottery wheel (radius 25.0cm) without slipping. Calculate: a) the...

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 theta 0 = -90°. The disk then undergoes constant angular acceleration. After accelerating for 3.1 s, the reference line has been moved part...

Just checking to see fi I did the math right: During the spin-dry cycle of a wash, the motor slows down from 95 rad/s to 30 rad/s while turning the drum through an angle of 402 radians. What is the magnitude of the angular acceleration of the motor? = 1/2(Wo + W)t 402 = 1/2(95 +...

This is the last problem that is frustrating me... A wheel, starting from rest, rotates with a constant angular acceleration of 1.20 rad/s2. During a certain 5.00 s interval, it turns through 32.5 rad. (a) How long had the wheel been turning before the start of the 5.00 s interval? (b) What...

This problem states: A human centrifuge takes 1.0 min to turn through 20 complete revolutions before reaching final speed. They are asking for angular acceleration (a) and angular speed in rpm (b). The answer to a is 40 rev/min^2 The answer to b is 40 rev/min -I'm have the formulas for...

there are two blocks on a trapizoid one on the top and one on the side with the slope a wire that goes throu a pully connects the two. determin the the acceleration of the two blocks. block one =m1 block two = m2 pully =m with radius r Ufriction =.36 what i have so far is sum of...

A 3 kg mass and a 4 kg mass are attached to either end of a 3 m long massless rod. If the system is rotated about the center of mass by a force of 7 N acting on the 4 kg mass, (perpendicular to the rod), what will the size of the angular acceleration of the system be? I used angular...

A fish takes the bait and pulls on the line with a force of 2.2 N. The fishing reel, which rotates counterclockwise without friction, is a solid cylinder of radius 0.049 m and mass 0.82 kg. What is the angular acceleration of the fishing reel? I used angular acceleration = RT/I, and got...

I have a shaft with radius "r" running at a certain RPM. how can i determine the angular acceleration of the shaft. Do i need any other parameters as well? Can i say that the angular acceleration can be (w^2*r), w is the angular velocity, r being the radius. thanks