Angular velocity Definition and 841 Threads

Hi, We have been studying centripetal forces and accleration in my class, and my teacher has shown me how to derive centripetal acceleration as v^2/r using change in velocity over time. I recently got into angular velocity vs. linear velocity in my math class, and I know that angular...

Homework Statement A wad of sticky clay with mass 2.45 kg and velocity vi = 52.0 m/s is fired at a wheel of moment of inertia 1.2 kg m2 and radius R = 1.26 m. The wheel is initially at rest and is mounted on a fixed horizontal axle that runs through its center of mass. The line of motion of...

Homework Statement Find the hours it takes for the Earth to rotate in one day if the mass is reduced to 2/3 of its original mass and it is shrunk to 3/4 its original size.Homework Equations L=IωThe Attempt at a Solution To start this problem I assumed that angular momentum is conserved from...

The text for the intro physics class I'm taking is the first edition. I have noticed some errors in earlier chapters, and was wondering if this problem here is also an error? Not sure yet. The question is about a CD. It says to find the angular velocity, and gives two points on the radius...

Homework Statement A mass M=2kg moves at a constant speed constrained by a string to move in a circle with radius .5m on a frictionless table. The tension in the string is 5N. What is the tangential speed? What is the angular velocity? What is the angular acceleration? How much work...

Homework Statement A diver can change his rotational inertia by drawing his arms and legs close to his body in the tuck position. After he leaves the diving board (with some unknown angular velocity), he pulls himself into a ball as closely as possible and makes 2.34 complete rotations in...

Homework Statement I need help with this question: http://img804.imageshack.us/img804/2278/unledsbg.jpg For a, I got omega = 18.63 rad/s by using methods of conservation of energy. Can someone tell me if I did this right? If not, please help me out! To be honest, I thought I had to use...

Homework Statement I'd like to know if I am on the right track. I'm not sure if I am doing this right... Find the angular velocity, in rad/s, of the Earth due to its daily spin on its axis, the Earth due to its yearly motion around the sun, and our moon due to its monthly motion around the...

Homework Statement The once-popular LP (long-play) records were 12 inches in diameter and turned at a constant 33(1/3) rpm. Find the angular speed of the LP in rad/s and its period in seconds. Homework Equations 1 rpm=((2∏)/60) The Attempt at a Solution for ω i got 3.49 I...

a particle A has a circular movement with radius R and angular velocity of 2w, a particle B has a radius of 2R and an angular velocity of w, both velocities remain constant. particle B rotates clockwise and particle A rotates anticlockwise for an interval of t = n/(2w) what angle is formed by...

http://img221.imageshack.us/img221/522/fisikaumn.jpg A small ball (mass = 0,1 kg) tied to a non-stretchable thread moves over a smooth horizontal plane. The other end of the thread is being drawn into a hole O with a 0,8 Newton force so that the ball moves with a constant radius 0,4 m And...

Homework Statement What is the power the drill can supply at the two points of interest(The intersections at the axis') This is a direct translation of the dutch problem. So basically what's going on is we made measurements of the RPM and angular displacement of our mechanical system...

I am having dificulty understanding the equation to angular velocity. w=alpha/time so if given this statement, (this is not homework). A helicopter blade is rotating at 400 rev per minute, find angular velocity in radians per minute. So i have w=400/1 minute. great, so that's it? or...

Homework Statement Wheel A of radius ra = 8.9 cm is coupled by belt B to wheel C of radius rc = 30.7 cm. Wheel A increases its angular speed from rest at time t = 0 s at a uniform rate of 8.6 rad/s2. At what time will wheel C reach a rotational speed of 93.0 rev/min, assuming the belt does not...

1. Homework Statement A solid sphere of mass m rotates uniformly in a horizontal circle suspended from a fixed point on a cord of length L and negligible mass. The cord makes an angle theta from the vertical. What is the angular velocity? 2. Homework Equations Torque= (Rotational...

Homework Statement Calculate the angular acceleration and angular velocity of a 2kg object rotating in a circle of 1.5m radius in a time of 3s. Homework Equations w=v/r 2*pie*r The Attempt at a Solution Now i don't know how to fully work this out, not sure how to apply the...

Hello. Sorry for my English There are R - rotation matrix (that performs transformation from associated coordinate system IE to static coordinate system OI) and \omega - angular velocity. The matrix R depends on parameters \xi (for example, Euler angles). I need to express \omega as function...

A ball of mass 0.25kg is whilred around in a horizontal circle on the end of a string of the length 0.03m, and completes 5 revolutions per second what is the angular velocity of the ball? is it right to use angular velocity = 2 pi F giving me a answer of 31.4 ms

A disk of radius R and mass M is mounted with its axis vertical.It is inially at rest.A bullet of mass m and velocity v is fired horzentally and tengential to disk .It enters the disc at its perimeter.What angular velocity will be acquired by disk? 1=mv/(m+M)R 2=mv/(2M+m)R 3=Mv/mR...

Homework Statement Determine the observed angular velocity from the origin of the reference frame for an object shown in the figure. The observed angular velocity is defined as the rate with which the observed direction on the object (measured in radians) changes in time. Hint: The observed...

I don't get radians. I understand it's a constant, ie: circumference/radius = 2pi because 2*r*pi equals circumference BUt I don't get why it is so damn handy for measuring angles! THe formula for angular velocity is \omega*r=(2pi/t)*r where omega=change in angle divided by time. what the...

Here is a link to page in a book which contains an example problem: http://imgur.com/OPrlw.jpg" In the book, they work out the natural frequency of a hydraulic cylinder and come out with an answer in rad/sec. This number is then inverted to get a time constant, and the resultant unit is...

Homework Statement A meter stick is freely pivoted about a horizontal axis at the 94.7 cm mark. Find the (angular) frequency of small oscillations, in rad/s Homework Equations I=Icm+md^2 \Sigma \tau=I \alpha mg*sin(\Theta)=-I(d^2\Theta/dt^2) The Attempt at a Solution 5.37 rad/s

Homework Statement A ball of mass 0.13 kg, is whirled round in a horizontal circle, on the end of a string of length 0.60m, and completes 5 revolutions per second. Calculate: (a) the angular velocity of the ball; (b) the speed of the ball; (c) the tension of the string. Homework...

How does the angular velocity change with increase in the mass? For example : if there is a shaft rotating at 1500 Rpm , then if a disc of 5 kg is fastened , does the angular velocity of the disc will be same as 1500 RPM , and what happens to the RPM if the disc mass is 50Kg.

Homework Statement the spring oa is fixed from one end o to the bottom of a vertical circular smooth tube and from its other end to a slider a of mass m which can slide smoothly along the tube initially started from rest at a . find : i) angular velocity II) angular acceleration at any...

Homework Statement A hollow cylinder of length L and radius R, is madeout of a non-conducting material, is charged with a constant surface charge σ, and is rotating, along its axis of symmetry, with an angular velocity w(t) = αt. Q:What is the magnetic field inside the cylinder...

if I were to throw a boomerang in an experiment, how would i find the angular velocity? How would i be able to check that my angular velocity is correct?

Homework Statement A wind turbine is initially spinning at a constant angular speed. As the wind's strength gradually increases, the turbine experiences a constant angular acceleration 0.127 rad/s2. After making 2790 revolutions, its angular speed is 155 rad/s. (a) What is the initial angular...

I've got a synoptic paper coming up and for the life in me I can't remember how to do some basic dynamics! Homework Statement A massless rope is wrapped several times around a solid cylinder of radius R = 20 cm, and mass M = 20 kg, which is at rest on a horizontal surface. Someone pulls 1 m...

Homework Statement Hi guys, We did a lab experiment in school, where we attached some weights to a hanger, and attached this to a pulley, for each weight attached, we dropped the weight hanger and recorded the time taken for the weight to pass through a sensor, this sensor system made use...

Homework Statement A circular coil of area A with N turns rotates at an angular velocity w about an axis perpendicular to its own axis and to a uniform magnetic field B. Find an expression for the induced EMF in the coil in terms of B, N, A, w and time t. What is the orientation of the coil...

Homework Statement a cylinder, r= 0.5 m with a mass 100 kg which is hanging 50 m above the ground. A rope of negligible mass which is 25 m long is wrapped around the cylinder. At the end of the rope a 10 kg mass is hanging. The hanging mass will fall and the rope will spin off the cylinder...

Homework Statement A solid rectangle of uniform density has one corner at the origin. It has a mass of 50 kg. The rectangle has a length of 4 m in the z-direction, a length of 3 m in the y-direction, and a length of 2 m in the x-direction. The pivot is at the center of mass. There is a 50 N...

1. A merry go round (1000kg) initially at rest with a diameter of 4m is pushed with a tangential force of 500N for 10s. Find the angular velocity, angular momentum, and rotational kinetic energy. After this, a little girl (mass - 1 kg) is placed on the rim of the merry go round.. Calculate the...

I just got done taking a test and on of the problems read: A rotor is turning at 200 rpm and has an angular acceleration of -0.015w rads/s^2. How many seconds before the rotor is at 200rpm. How many revolutions before the rotor comes to rest. Here is my method for solving: w initial = 200rpm...

Hi Doing some revising for my exams with past papers. I just need some help to begin this question. Q The shaft of diameter 0.25 is rotating at 3000 rev/min Determine a) The angular velocity b) The linear speed of a point on the circumference of the shaft c) The angular...

I've got a question that I am stumped on right now Show that if the Galactic angular velocity \Omega of an interstellar cloud is > sqrt(4piG\rho/3), the cloud can not collapse in the radial direction. Estimate \Omega and compare it to the rotation rate of the Galaxy.

Homework Statement http://img690.imageshack.us/img690/5381/screenshot20110430at121.png Homework Equations v=r*omega The Attempt at a Solution v=0.5m/s r=0.2m omega=0.5/0.2 omega=2.5rad/s (i) Is this correct for the angular velocity of the disk? (ii) The velocity of the center of the disk...

Homework Statement A meter stick is suspended vertically at a pivot point 25 cm from the top end. It is rotated on the pivot until it is horizontal and then released from rest. What will be its maximum angular velocity (in radians/second)?Homework Equations I began by setting up a conservation...

1. A light, hollow cone is filled with sand set spinning about a vertical axis through its apex on a frictionless bearing. Sand is allowed to drain slowly through a hole in the apex. Calculate the fractional change in angular velocity when the sand level has fallen to half its original value...

Homework Statement I am asked to find the angular velocity of a falling rod in the instant that the rod meets the horizontal. The system is set up in this image: The only force acting on the rod is gravity Homework Equations U = (1/2)MgL K = (1/2)Iw2 Kf + Uf = Ki + Ui The...

Homework Statement Torsional spring constant k=33 Nm/rad It is undeflected when it is in the vertical position, it weighs 6.4 kg When the bar is released from the horizontal position from rest, determine the angular velocity \omega as it passess the vertical position. We can assume that it is...

Homework Statement A 4.3 m diameter merry-go-round is rotating freely with an angular velocity of 0.78 rad/s. Its total moment of inertia is 1760 kg m^2. Four people standing on the ground, each of mass 67 kg, suddenly step onto the edge of the merry-go-round. 1)What is the angular velocity...

Hello, I have been set a question for homework that ask's "calculate the tangential velocity (v) and the angular velocity (omega) of our moons orbit". The teacher has lead me to believe that tangential velocity is just regular velocity? is this correct?. I understand what angular velocity is...

The Earth has a radius of 6.38 x 106 m and turns on its axis once every 23.9 h. (a) What is the tangential speed (in m/s) of a person living in Ecuador, a country that lies on the equator? (b) At what latitude (i.e., the angle in the figure, in degrees) is the tangential speed 1/4 that of a...

The radius of the circle traced out by the second hand on a clock is 6.00 cm. In a time t the tip of the second hand moves through an arc length of 19.0 cm. Determine the value of t in seconds. Ok, so I know how to find θ: s/r. And I know that Angular Velocity is θ/Δt. I am confused on how...

Homework Statement A satellite moves in a circular orbit around the Earth at a speed of 6.6 km/s. Determine the satellite’s altitude above the surface of the Earth. Assume the Earth is a homogeneous sphere of radius 6370 km and mass 5.98 × 1024 kg. The value of the universal gravitational...

I thought of this today while studying relativity. Imagine a very large disc spinning with an arbitrary angular velocity. Perhaps w=57 rad/s (this is the speed of a CD, got this from a random physics text, whatever, the speed is really not important).. The speed of light is c=3*10^8 m/s...

Homework Statement Your bicycle tires have a radius of 0.33 m. It takes you 850 seconds to ride 14 times counterclockwise around a circular track of radius 73 m at a constant speed. (a) What is the angular velocity of the bicycle around the track? (b) What is the magnitude of the angular...