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Angular Momentum

Angular Speed after a Collision

Please show all work. A solid wood door, 90.0 cm wide by 2 m tall has a mass of 35kg. It is ajar and at rest. A ball with a mass of 500g is thrown perpendicular to the door with a speed of 20m/s and hits the door 60cm from the hinged side. The ball rebounds with a speed of 16 m/s along the same line. What is the angular spe

Calculating common angular speed

Two wheels with rotational inertias of 1.0 kg m^2 and 1.5 kg m^2 are rotating on the same axis at 20 rads and 12 rads respectively, in opposite directions. If the wheels are suddenly coupled together, find the common angular speed of the wheels after being coupled.

Totational Motion: Bullet stricks a hanging rod.

A thin uniform rod of mass 400 g and length 60.0 cm is suspended from a pivot and is free to rotate about it in any direction. A bullet strikes the rod at a distance of 46.0 cm from the pivot and gets stuck in it. The bullet was initially moving at a speed of 300 cm/s and was spinning about its forward-backward axis at 17.0 rad/

Rotational motion: A stationary rod is struck at one end.

A uniform rod is resting along the x-axis on a frictionless table with its center of mass at the origin. It is suddenly struck near one end by a blow in the +y direction. The mass of the rod is M=175 g and the impulse applied by the blow is K=74 g m/s. Immediately after the rod is struck, (a) what is the velocity of the cente

Rotational Motion: Torque, angular acceleration, velocity

A 3.50 kg counterweight is attached to a light cord, which is wound around a spool . The spool is a uniform solid cylinder of radius 8.00 cm and mass 1.40 kg. (a) What is the net torque on the system about the point O? (b) When the counterweight has a speed v, the pulley has an angular speed w= v/R. Determine the total a

Miscellaneous physics question

1. Competitive divers pull their limbs in a curl up their bodies when they do flips. Just before entering the water, they fully extend their limbs to enter straight down. Explain the effect of both actions on their angular velocity. What is the effect of these actions on their angular momentum? 2. What is the final velocity

Tension, Force, Momentum, Velocity, Temperature, Energy

1. A 9kg hanging weight is connected to a string over a pulley to a 5kg block that is sliding on a flat table. If the coefficient of kinetic friction is 0.15, find the tension in the string. 2. A 50kg ice skater is moving at 5m/s when she grabs the loose end of a rope, the opposite end of which is tied to a pole. She then mo

Rotational Dynamics Simple Harmonic Motion

A woman stands at the center of a platform. The woman and the platform rotate with an angular speed of 1.30 rad/s. Friction is negligible. Her arms are outstretched, and she is holding a dumbbell in each hand. In this position the total moment of inertia of the rotating system (platform, woman, and dumbbells) is 6.66 kg·m2. By

Calculating velocity and angular velocity

Please help with the following problem. Provide step by step calculations fo reach. A uniform cylinder (A) has a mass ( m = 3 kg ), radius ( r = 150 mm ), and can roll without sliding on a cart ( C ) of mass ( M = 5 kg ). Cylinder (A) is attached to a spring (AB) of stiffness (constant) k = 100 N/m as shown (attached). The s

Angular Velocity and Distance Problems

A 1.62 oz golf ball with a 1.70 in. diameter is hit by a club at point P. Velocity magnitude of the ball's center of mass is 180 ft/s after the impact. What is the angular velocity of the ball? (h = 0.2 in.) A 1 oz. bullet with a horizontal velocity of 350 ft/s strikes a circular disk. The bullet is embedded into the disk aft

Rotation of a Diver

A diver can change her rate of rotation in the air by "tucking" her head in and bending her knees. Lets assume that when she is stretched out straight she is rotating at 1 revolution per second. Now she goes into the "bend and tuck", effectively shortening the length of her body in half. What will her roation be now? a. 5Hz

Running on circular platform

Suppose a 60kg person stands at the edge of a 6.0m diameter circular platform, which is mounted on frictionless bearings and has a moment of inertia of 1800kgm^2. The platform and runner are initially at rest. Calculate the angular velocity of the platform if the runner begins to run 4.2m/s.

Rotating a Professor on a Turntable

Hi I need you help for two questions. 1. A professor steps onto a stationary turntable while holding a rotating bicycle wheel that is rotating with an angular velocity of 15 rad/s pointing upward. The wheels axis of rotation goes through the axis of the turntable. The rotational inertia of the wheel is 1.5 kg m^2 and the co

Mechanics: Dynamics (Translational and rotational motion).

1. Two equal weights of mass M each are connected by a cord passing over a frictionless pulley of mass mp and radius r. An additional weight of mass m is placed on one of the weights of mass M. Derive the expression for: a) system acceleration a; b) cord tensions. 2. A helicopter rotor blade can be considered a long thin

Magnitude of Angular Momentum

1. A car of mass 1000 kg moves with a speed of 50 m/s on a circular track of radius 100 m. What is the magnitude of its angular momentum (in kg.m^2/s) relative to the center of the racetrack? 2. A Body oscillates with simple harmonic motion along the x-axis. Its displacement varies with time according to the equation x=5 sin

Angular momentum of a space station

A space station is constructed in the shape of a hollow ring of mass 5.00 x 10^4 kg. Members of the crew walk on a deck formed by the inner surface of the outer cylindrical wall of the ring, with radius of 100m. At rest when constructed, the ring is set rotating around its axis so that the people inside experience an effectiv

Angular momentum of a rotating rigid object

A uniform solid sphere of radius 0.500 m and mass of 15.0kg turns counterclockwise about a vertical axis through its center. Find its vector angular momentum when its angular speed is 3.00 rad/s. I think I have worked this problem correctly. (See attachment) Please check my answer and confirm if in correct please point ou

Mechanics, rotation, angular deceleration. Part 3

A flywheel initially rotating at a speed of 800 rev/min, is brought to rest with uniform angular deceleration in 6’s c. At what time will both the radial and tangential components of acceleration be equal in magnitude?

Angular Velocity of a Block on a Heated Spinning Rod

A 1.10 m-long massless rod is pivoted at one end and swings around in a circle on a frictionless table. A block with a hole through the center can slide in and out along the rod. Initially, a small piece of wax holds the block 10.0 cm from the pivot. The block is spun at 50.0 rpm, then the temperature of the rod is slowly increa

Bohr Quantium Condition

A particle of mass m is attracted to the origin by a force proportional to the distance from the origin F = -kr. Assume that it moves in circular orbit of radius r. a) Use Newton's law to show that its kinetic energy 1/2mv^2 equals its potential energy 1/2kr^2. b) Use Bohr quantum condition on the angular momentum (L = nh

Conservation of angular momentum when a system changes configuration.

A uniform cylinder, mass M= 12 kg, radius R= .36 m, is initially rotating about a vertical axis through its center at angular velocity wo= 6.6 rad/sec. Now two small (point masses), each of mass m= 2 kg, are dropped onto and stick to the cylinder, each at distance r= .24 m from the axis. SEE ATTACHMENT for diagram. Find wf, t


Why does Earth precess? Could you explain in sentences not just shown the graph.

Moment of Inertia for Figure Skater

A figure skater during her finale can increase her rotation rate from an initial rate of 1.12 revolutions every 1.88 s to a final rate of 3.15 revolutions per second. If her initial moment of inertia was 4.73 kg* m2, what is her final moment of inertia?

Rolling, Torque , and Angular Momentum

Rolling, Torque , and Angular Momentum 1. A constant horizontal force of magnitude 10 N is applied to a wheel of mass 10 kg and radius 0.30 m as shown in the figure below. The wheel rolls smoothly on the horizontal surface and the acceleration of its center of mass has magnitude 0.60 m/s^2. ( a) what are the magnitude and