Disk Definition and 819 Threads

Homework Statement I'm wondering how to write the equation of constraint for a solid disk (mass m, radius R) that is attached to a spring (spring constant k) and rolls without slipping. Any suggestions? Homework Equations there are no equations to use, but this has to do with lagrange's...

Hey guys! I'm doing my B.S thesis (Mech. Eng.) and I've come across the problem of a rolling disk with friction. Imagine a disk in real world rolling on a flat surface with no external force or torque applied to it except for the interaction of the surface (Normal, friction, etc.). Now...

A potter has a stone disk of radius 0.483 m and mass 101 kg rotating at 71.9 rev/min. The potter stops the wheel in 6.54 seconds by applying a wet towel against the rim with a radially inward force of 103 N. Find the effective coefficient of kinetic friction between the whell and the wet towel...

Volumes: The Disk Method [Resolved] 1. If the area bounded by the parabola y = H - (H/R^{2})x^{2} and the x-axis is revolved about the y-axis, the resulting bullet-shaped solid is a segment of a paraboloid of revolition with height H and radius of base R. Show its volume is half the volume of...

Homework Statement A flat, uniform, disk, of radius 1.5 m and mass 10 kg, is rolling on its edge with a translational velocity of 12 m/s. What is the kinetic energy of the disk? Homework Equations not sure which one but I'm guessing it's one of these two: K = .5(I)(w)^2 K =...

Homework Statement It's part of Kleppner and Kolenkow 7.4. See the attached picture. (The disk is rotating around the vertical "stick", not rotating towards it. (I have bad drawing skills) The question mainly asks what is the normal force on the disk. I am stuck trying to find the moment of...

Along the axis of a uniformly charged disk, at a point 0.6 m from the center of the disk, the potential is 91.4 V and the magnitude of the electric field is 86.5 V/m; at a distance of 1.5 m, the potential is 46.8 V and the magnitude of the electric field is 27.0 V/m. Find the total charge...

Homework Statement Consider a thin disk normal to the z-axis, of thickness dz and radius p centered on the axis of a dipole. a. Show that 0 = \oint \vec{B} \cdot d\vec{A} \approx (2\pi p dz)B_{r} + (\pi p^{2}) a (dB_{z} / dz), so B_{p} \approx (-p/2)(dB_{z} / dz) b. With B_z for a...

Homework Statement A disk has mass 3kg and outer radius 50 cm with a radial mass distribution (which may not be uniform) so that its moment of inertia is (2/7)mR^2. The disk is given a hard kick (impulse) along a horizontal surface at time t0. The kicking force acts along a horizontal line...

Homework Statement A solid uniform disk of mass 21.0 kg and radius 85.0 cm is at rest flat on a frictionless surface. A string is wrapped around the rim of the disk and a constant force of 35.0 N is applied to the string. The string does not slip on the rim. How much string has unwrapped from...

Homework Statement A disk with a mass of 4kg and a .20m radius is free to rotate about a horizontal axis. A 4.0kg mass and a 8.0kg mass are attached by a massless string, which is hung over the disk. If the string does not slip, what is the angular velocity of the disk after 2 seconds...

1.Provide the question and knowns A uniform disk turns at 3.7rev/s around a frictionless spindle. A nonrotating rod, of the same mass as the disk and length equal to the disk's diameter, is dropped onto the freely spinning disk. they then turn together around the spindle with their centers...

In future HDD will be replaced by solid state disk,SSD will become the mainstream. Solid State Disk （SSD）： it is a general definition to distinguish traditional mechanical drives which depends on complex mechanical parts and control circuits, bascially any drive with electronics storage media...

Homework Statement Find the electric field due to a Charged Disk at a distance of "d" which is in the disk's axis direction. The charge has it's maximum value at disk's center and decreases towards the edges. I have the solution for uniformly charged disk but I can't figured it out for the...

Homework Statement A computer hard disk starts from rest, then speeds up with an angular acceleration of 198 rad/s2 until it reaches its final angular speed of 7683 rpm. How many revolutions has the disk made 10.7 s after it starts up? Homework Equations t=wf/a delta0=wi*t+(1/2)(a)t^2...

Homework Statement What is the rotational inertia of a solid iron disk of mass 46 kg, with a thickness of 6.31 cm and radius of 19.4 cm, about an axis through its center and perpendicular to it? Homework Equations either 1/2MR^(2) or I = sigma (1->N) Mi x Ri^(2) The Attempt at a...

Homework Statement (Actually, this is not a homework, but a project I'm trying to accomplish but I have almost forgotten physics...) There is a disk weighting 100kg with a radius of 0.6 meters. What would be the torque needed to accelerate the disk from 0 rpm to 6 rpm in 10 seconds...

Hello, I have a problem about my disk driver: My CD disk driver doesn't appear in the "my computer" window. when i noted that error, I checked in driver manager but it didn't show any error. Then i got an idea to restart the computer and the disk driver appeared for a short time and...

Homework Statement Determine the moment of inertia of a think disk of mass M, with inner radius A and outer radius B, when rotating about an axis perpendicular to the plane of the disk and through its center.Homework Equations The equation of moment of inertia for a disk is I = (m*r^2)/2 my...

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...

Can someone explain to me when you should user the Shell / Disk / Washer methods? I don't understand how to determine which method to use.

Spinning Disk problem. Due tomorrow! Help please! A disk with a diameter of 0.1 m is spinning about an axle perpendicular to the disk and running through its center. a) How many revolutions per second would it have to rotate in order that the acceleration of the outer edge of the disk be 14...

Reducing it to three questions, because I'm pretty confident on the others. 9. Find the volume of the solid generated by revolving about the line x = -1, the region bounded by the curves y = -x^2 + 4x - 3 and y = 0. --- I graphed everything, and then translated the graph 1 to the right making it...

Last few I can't seem to do, but on the others, can someone check my answers?. The last few I need help getting through. 1. Find the volume of the solid formed when the region bounded by the curves y = x^3 + 1, x = 1 and y = 0 is rotated about the x-axis. My answer: int(pi(x^3+1)^2,x,-1,1)...

Homework Statement A manufacturer drills a hole through the center of a metal sphere of radius 5 inches. The hole has a radius of 3 inches. What is the volume of the resulting metal ring? Solution: You can imagine the ring to be generated by a segment of the circle who equation is x^2...

Hi, I know the following calculation is incorrect but have been unable to find the error. The calculation is to integrate I = \int z^2 \sqrt{r^2-z^2}dz. Trying u-substitution: u = \sqrt{r^2 - z^2} z^2 = r^2 - u^2 2z dz = - 2udu dz = \frac{-udu}{z} =...

I understand the answer to this part of the problem intuitively but there's definitely something in the math that I'm missing-- Homework Statement Along the axis through the center of a charged disk, for a point P at a distance x from the center, the potential will be...

Homework Statement Okay, I totally do not understand how to derive the electric field made by a dipole or a line or a ring or etc. Homework Equations When finding the electric field, when you make an estimate, saying that the test charge is very far away, it should be similar to kQ/r^2...

Homework Statement A solid uniform disk of radius 0.250 m and mass 55.0 kg rolls down an incline that makes an angle of 15 degrees with the horizontal. The disk starts from rest from the top of the ramp. Find the speed of the disk's center of mass when it reaches the bottom of the ramp(linear...

Deleting a file that "can not read from the source file or disk" I downloaded a torrent file the other day and half way through the download i decided i didn't want to finish downloading so i deleted the file using a command prompt on bittorrent. Now the file (which is on my desktop) is deleted...

Hi, Homework Statement The electric field of a uniform charged disk at a point on its axis at a distance x from the disk is given by E = 2k_e\pi\sigma(1-\frac{x}{\sqrt{x^2+R^2}}) where R the radius of the disk and \sigma the surface charge density. In my notes it says that when x\gg R, that is...

Hello to all...first post here! I need to compute 3D (x,y,z) points around the surface of a pipe. By pipe I mean something like an underground pipeline. Let's say I'm given the bottom point of the pipe in x,y,z coordinates, the diameter of the pipe (say 12 feet), and the inclination or...

when I was running a standard check on my HDD I found when I ran my disk filler (to completely delete my files PM me if you don't understand) i found 2Gb would not write i checked the binary point only to find it was empty.. absolutely nothing (just before anyone says my OS is on a separate part...

Help me….my hard disk is damaged! Hi everyone , I am employed as a manager in a firm. I have a problem that I had like to talk about. My system was working fine the other day, but while copying a file by nero….the system hanged and I had to restart it. But I got a disk boot failure error. Then...

Hello! I need to know whether the hard disk is on or off during the following states (in windows vista): -During Standby -During Hybrid Standby -During Hibernation Note that I mean by on that the hard disk is spinning regardless if it is reading,writing or doing nothing. Please I need...

I'm confused when to use the shell method vs. the disk method Specifically in this problem: If the region encolsed by the y-axis, the line y=2 and the curve y=\sqrt{x} is revolved around the y-axis, the volume of the solid generated is: However when I use the shell method and the disk...

[SOLVED] Force needed to make a disk climb a step Howdy ho. First off, let me say that I'm a newbie here, and I'm not sure if this is the correct place to put this doubt. Here's the deal: Homework Statement We have a disk, and we need to know the force F needed to have it climb the step...

I have attempted to solve this question and I got stuck at the last part. Here you go. A uniform solid disk is set into rotation with an angular speed X about an axis through its center. While still rotating at this speed, the disk is placed into contact with a horizontal surface and...

Homework Statement A curcial part of a piece of machinery starts as a flat uniform cylindrical disk of radius R0 and mass M. It then has a circular hole of radius R1 drilled into it. The hole's center is a distance h from the center of the disk. Find the moment of inertia of this disk (with...

Homework Statement http://urlcut.com/katrolafbeelding.gif What is the accelaration of a point on the circumference of the disk? Homework Equations \tau = F.R = I.\alpha I = M.R²/2 a = R.\alpha F(z) = m.g The Attempt at a Solution The mass exerts a force F(z) = m.g on...

hi, everyone. Do anyone here can suggest where, which book or website can learn more bout the theory behind the magnetic hard disk, and it current technology? i.e. spintronic...

For some time I've been thinking of making a round disk shaped model aircraft that would appear to have low drag, maximum internal carrying space, and maximum load carrying ability. As you can guess, there is little available on such a design, other than the Pancake, built at the end of WWII...

Homework Statement A uniform disk of radius 0.12 m is mounted on a frictionless, horizontal axis. A light cord wrapped around the disk supports a 1 kg object, as shown in the figure from rest the object falls with a downward acceleration of 2.3 m/s^2.The acceleration of gravity is 9.8 m/s^2...

Problem: A disk rotates about its central axis starting from rest and accelerates with constant angular acceleration. At one time it is rotating at 12 rev/s; 69 revolutions later, its angular speed is 33 rev/s. Calculate (a) the angular acceleration, (b) the time required to complete the 69...

Homework Statement A disk of radius 21.0cm is free to turn about an axle perpendicular to it through its center. It has very thin but strong string wrapped around its rim, and the string is attached to a ball that is pulled tangentially away from the rim of the disk (the figure ). The pull...

Homework Statement 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...

Does anyone know of any programs/methods for this? I had a disk crap out on me over the weekend and there are some email I didn't have backed up that I would like to try and recover. I tried repairing it with chkdsk and the Windows Recovery Console to no avail. Thanks...CS

Is there a general solution for gravity force in Alderson Disk system? Given: Alderson Disk system, disk inner radius R1, outer radius R2, thickness T, density Rho, star mass M (irrelevant due to superposition?). http://orbides.1gb.ru/orbf/ad1.jpg How to find amount and direction of...

Homework Statement During normal operation, a computer's hard disk spins at 5400 rpm. If it takes the hard disk 8.4 s to reach this angular velocity starting from rest, what is the average angular acceleration of the hard disk in rad/s2? Homework Equations ? The Attempt at a...

Homework Statement During normal operation, a computer's hard disk spins at 7200 rpm. If it takes the hard disk 3.7 s to reach this angular velocity starting from rest, what is the average angular acceleration of the hard disk in rad/s2? Homework Equations Wav = \varthetaf -...