Angular velocity Definition and 841 Threads

Homework Statement Suppose you were kidnapped and held prisoner by space invaders in a completely isolated room, with nothing but a watch and a pair of shoes (with shoelaces of known length). Explain how you might determine whether this room is on Earth or on the moon. Homework Equations...

Homework Statement A body with moment of inertia 20kgm^2 is rotating about a fixed axis with an angular velocity of w(t)= 3t^2-4 a. Through what angular displacement will the body move in the first 3 seconds b. What is the new torque exerted on the object at t=2 Homework Equations...

OK...this is a really trivial question, but I hope someone can help me here. I am working on building a segway-style robot that balances on two wheels, but I am having some difficulties integrating the data I receive from my gyro sensor. The sensor gives me the angular velocity, and I know...

Homework Statement A disk accelerates with a constant angular acceleration of 2.0 rad/s2. If the initial angular velocity is 5.0 rad/s, what is the angular velocity of the disk after rotating though an angle of 11.0 radians? a = 2 rad/s^2 vo = 5 rad/s Theta = 11 rad Homework...

Homework Statement A turntable rotates about a fixed vertical axis, making one revolution in 10s. The moment of inertia of the turntable about the axis is 1600kgm^2. A man, James Bond, of mass 120kg, is at the center of the turntable and begins to run out along a radius of the device. Treat...

Homework Statement Suppose we are in deep space and there's a particle of mass m and a sphere of radius R of mass M. Suppose also that the sphere is initially at rest while the particle is moving with a constant velocity v_0. The particle collide with the sphere in a position such that the...

This my first post on this very helpful forum. So are angular displacement, velocity, and acceleration actually vectors? My Physics book does not really give me a straight answer. Plus, if they are, why do they not have the classic vector notation of the arrow above \theta, \omega, and...

Homework Statement I'm working on a problem in which I have to calculate the centrifugal force. I know the equation and everything, I'm just stuck on what units my angular velocity should have. Homework Equations \vec{F_{cen}}=-m\omega\times(\omega \times r') The Attempt at a...

Homework Statement A rigid body is rotating about a fixed axis through the origin. The angular velocity is \omega\hat{k} where \omega is positive. What is the unit vector in the direction of the velocity of a point on the body located on the positive y axis? The Attempt at a...

Homework Statement Using your data from trial one, calculate angular velocity w, and angular acceleration, a My data from trial one is period of rotation=.791s Homework Equations w=(change in angle/change in time) a=(change in angular velocity/ change in time) The Attempt at a...

For a capacitor in an AC circuit, does \omega = \frac{1}{RC} always? I have voltages such as Vg = 2cos(105t) V. When finding the capacitance using the formula C = \frac{1}{jwc} would I use \omega = 105 or would I use \omega = \frac{1}{RC}?

Homework Statement A puck with mass 0.28 kg moves in a circle at the end of a string on a frictionless table, with radius 0.75 m. The string goes through a hole in the table, and you hold the other end of the string. The puck is rotating at an angular velocity of 18 rad/s when you pull the...

Homework Statement A disk is rotating freely at 1,000 revolutions per minute about a vertical axis through its center. A hoop with twice the mass of the disk and the same radius as the uniform disk is poised exactly above and is initially at rest. The hop is dropped gently upon the disk so...

Homework Statement A 6.90 coin is placed 13.0 from the center of a turntable. The coin has static and kinetic coefficients of friction with the turntable surface of = 0.740 and = 0.450. What is the maximum angular velocity with which the turntable can spin without the coin sliding...

Question: An Australian bushman hunts kangaroos with the following weapon, a heavy rock tied to one end of a light vine of length 2.0m. He holds the other end above his head, a point 2.0m above the ground level, and swings the rock in a horizontal circle. The cunning kangaroo has observed that...

A small 0.870-kg object moves on a frictionless horizontal table in a circular path of radius 7.80 m. The angular speed is 9.85 rad/s. The object is attached to a string of negligible mass that passes through a small hole in the table at the center of the circle. Someone under the table begins...

Homework Statement The minute hand of big ben is made of copper, has a length of 4.27 meters, and a mass of 101.6kg. The hour hand is made of gunmetal, has a length of 2.74m, and a mass of 304.8kg. Assume that each hand is a uniform rod and rotates about one end. Use a cartesian coordinate...

Homework Statement A hamster runs in its wheel for 4.5 hours every night. If the wheel has a 6.8 cm radius and its average angular velocity is 3.0 radians per second, how far does the hamster run in one night? Homework Equations angular velocity = ang displacement / time The...

A 40kg child takes a ride on a Ferris Wheel that rotates 4 times each minute and has a radius of 9m. I firgured that angular velocity is .419 rads/sec I figured that tangential velocity is 3.77m/sec I figured that centripetal acceleration is 1.58m/sec^2 Questions a)What force in N does...

Hi, I have a little problem. I recently got the nerve to try and teach myself all of the physical properties necessary to program a physics engine (the insomnia is a DIFFERENT problem). It's going much better than I could've hoped (considering I started a few days ago). My knowledge of physics...

Homework Statement A billiard ball is struck by a cue as is shown in the figure. The line of action of the applied impulse is horizontal and passes through the center of the ball. The initial velocity v0 of the ball after impact, its radius R, its mass m, the acceleration due to gravity g, and...

Homework Statement The radius of the Earth's very nearly circular orbit around the sun is 1.5*10^11. Find the magnitude of the Earth's angular velocity in rad/s. Homework Equations The Attempt at a Solution For this problem, I have no clue how to go about solving this. help would...

Homework Statement A runner of mass 51.0 kg runs around the edge of a horizontal turntable mounted on a vertical, frictionless axis through its center. The runner's velocity relative to the Earth has magnitude 3.60 m/s. The turntable is rotating in the opposite direction with an angular...

The mass of a star is 1.1e31 kg and its angular velocity is 1.40×10-7 rad/s. Find its new angular velocity if the diameter suddenly shrinks to 0.17 times its present size. Assume a uniform mass distribution before and after. [Icm for a solid sphere of uniform density is 2/5 mr^2]. i have to...

A large horizontal circular platform (M=120.1 kg, r=3.45 m) rotates about a frictionless vertical axle. A student (m=73.3 kg) walks slowly from the rim of the platform toward the center. The angular velocity w of the system is 3.9 rad/s when the student is at the rim. Find w (in rad/s) when the...

Homework Statement I have this pole with mass M and length L which is on a flat table with no friction. Another particle, which has the same mass M hits him on its edge with velocity V, which is vertical to the pole. then, the particle sticks to the pole and they move together. I need to...

Homework Statement Supposed that the mass of certain spherical neutron star is twice the mass of the sun (1.991*10^30) and its radius is 13.5 km. Determine the greatest possible angular speed it can have so that the matter at the surface of the star on its equator is just held in orbit by...

HELP!a question on angular velocity Homework Statement A horizontal cylindrical rod is free to rotate about a vertical axis perpendicular to its length through its centre of mass. two beads of mass m and 2m are each a distance l from the axis of rotation and are tied together by a light...

Homework Statement To throw the discus, the thrower holds the discus with a fully outstretched arm and makes one revolution as rapidly as possible to give maximum speed to the discus at release. The diameter of the circle in which the discus moves is about 1.7m. If the thrower takes 1.0s to...

Homework Statement Here's the problem statement, uploaded onto google docs: http://docs.google.com/View?docid=d277r7r_48f97jqsgs Homework Equations The Attempt at a Solution i) L=r*p L=R*m*v I think that's the answer, b/c they don't give us any constants to work with, but...

Homework Statement During startup of a power plant, a turbine accelerates from rest at 0.43 \rm {rad/s^2}.How long does it take to reach its 3200 \rm {rpm} operating speed? How many revolutions does it make during this time? Homework Equations The Attempt at a Solution

Consider an electric dipole located in a region with an electric field of magnitude E pointing in the positive y direction. The positive and negative ends of the dipole have charges + q and - q, respectively, and the two charges are a distance D apart. The dipole has moment of inertia I about...

Homework Statement The following data are for the angular displacement of the knee in cycling measured in degrees. Using radian measure, compute the angular velocity and acceleration when the knee angle is 119.1 degrees. The sampling frequency was 50 Hz. What is a problem you may...

Hi, I need to resit some exams and I'v been having difficulty trying to solve this problem. Estimate the velocity and angular velocity of an empty pipe of mass (m)=1000kg, Diameter (d)=10mm, shell thickness (h)=1mm at the bottom of a slope of angle \theta=45^{}o and path length L=5000mm on...

Hi I am having trouble with a problem that involves angular velocity. The problem states: The rigid object shown is rotated about an axis perpendicular to the paper and through point P. The total kinetic energy of the object as it rotates is equal to 1.4 J. If M = 1.3 kg and L = 0.50 m, what...

Homework Statement Homework Equations w = 2PI f v = wr Time = 2PI R/V The Attempt at a Solution w = (2000/PI x 60) x 2PI = 66.66 Radians/Sec V = wr = 66.6 x 300 = 19998 ( Is this velocity of the winding drum) 19998/200 = 99.99 ( Velocity/200 reduction gearbox...

[SOLVED] Angular velocity Homework Statement The angular acceleration of a flywheel of a generator is given by a(t) = 6bt - 12ct2 What is the angular velocity at t when the initial velocity is w0? The Attempt at a Solution w = w0 + at = w0 + 6bt2 - 12ct3 This is wrong...

Homework Statement 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. a. What is the cylinder's initial angular Acceleration? b*. What is...

Hullo was wondering if anyone could help me. In dimensional analysis using then buckingham pi theorum, I'm not sure how to express an angular velocity in terms of basic dimensions (i.e M (mass), L (length), T(time), \Theta (temp). I know an angular velocity is revs/s or rad/s so its going to...

The angle through which a rotating wheel has turned in time t is given by \ theta = a t - b t^2+ c t^4, where theta is in radians and t in seconds. What is the average angular velocity between t = 2.0 s and t =3.3 s? If a = 9.0 rad/s, b = 16.0 rad/s^2, c = 1.6 rad/s^4 Homework Equations...

Homework Statement A flywheel is a solid disk that rotates about an axis that is perpendicular to the disk at its center. Rotating flywheels provide a means of storing energy in the form of rotational kinetic energy and are being considered as a possible alternative to batteries in electric...

Homework Statement Hi, I would just like to know if I'm on the right track with this one. I have two identical particles with a radius R and mass M. One is at rest and the other moves directly down with a velocity v0. The second particle hits the first particle slightly offset, so that the...

Homework Statement The 15kg plate shown above is able to roate on its axle which is supported on the the journal bearings at A and B. A bullet is fired into the plate providing it with an initial angular momentum of 9kgm/s. Find the angular velocity of the plate when it has rotated thropugh...

Homework Statement A uniform solid sphere of mass M and radius R hangs from a string of length R/2. Suppose that the sphere is released from an initial position making an angle of 45 degrees with the vertical. Calculate the angular velocity of the sphere when it swings through the vertical...

A rod of mass M, length L, and uniform density and thickness swings around a frictionless pivot at one end of the rod; the other end is free. The rod is held at angle θ below the horizontal and then released with no initial angular velocity, ω0=0. Find the linear acceleration a of the rod's free...

[SOLVED] Unstretched Spring and Angular Velocity Problem Homework Statement A disk of mass 73 kg is held by a spring of unstretched length 88 cm and stiffness constant 430 N/cm, and rests on a frictionless table. It is then orbited in a circle at angular velocity .675 rad/s. By how...

Homework Statement the problem is: A 3.0 m diameter merry go round with rotational inertia 120kgm^2 is spinning freely at 0.50 rev/s. Four 25kg children sit suddenly on the edge of the merry go round. a) Find th new angular speed, and b) detrmine the total energy lost to friction between the...

Homework Statement A spool of thin wire rotates without friction about its axis. A man pulls down on the wire with force of 14.9N. How long does it take to increase the angular velocity of the spool from 11.0rad/s to 35.0rad/s? Icm = 0.490kg*m^2 Inner radius, r = 0.280m Outer radius, R =...

A wheel turns with a moment of intertia of 16.0kg m^2 and has 10m N applied to it. if it starts from rest calculate the angular velocity. Also what is the kinetic energy 10seconds later? The wheels angular velocity i used T=IA, and solved for Angular velocity solving for a i got...

Homework Statement What is the angular velocity magnitude of member BC? Problem Figure Attached: Homework Equations V = w r Va= Vb + Va/b The Attempt at a Solution I thought the problem would be simple as I could use v=w r to calculate the velocity and then use the equation of relative...