Disk Definition and 783 Threads

How much is the CPU involved in disk operations. Let's say I have a long disk operation such as copying a large file for several minutes. When I look at the CPU utilization on my computer (Windows XP), it's pretty low; basically zero. So how involved in such an operation is the CPU? Does it just...

Call me paranoid if you will, but is there any handy tool that keep a track or can find out what program that has a possibility/ability of internet connection, has visited what directory by what time? It could be a stand alone software, could be something that comes with windows. Does anybody...

Hi, How to determine a threshold aperture, at which the diffraction begins to limit resolution of the sensor ? Which situation reflects that point: 1) Airy disk diameter / 2 = 2 x pixel pitch http://www.outbackphoto.com/dp_essentials/dp_essentials_02/essay.html" (third pixel detects the...

When you listen to music, you hear the beat, the melody, and the vocals all at once... and they all emanate from the same disk. How does all the noise sound so separate and distinct from one another regardless of whether its a rumbly bass or a piercing pitch? This confusion comes from my...

Dear members, Everytime i start the system i get the following message " One of your disks needs to be checked for consistency . To skip disk checking press any key within 10 seconds" I wish that my disk needs to be checked so i didnt press any key but automatically after the specified...

If a circular disk rotates about its centre, what will happen to its geometry. Since a spinning disk has velocity gradients, different regions of the disk must contract by different proportions. For example, a uniformly moving body undergoes length contraction and its new geometry is easily...

Homework Statement Bars BC and AB and dish OA are attached by a pin like in the picture. The dish has a constant angular velocity \omega\_{0}. Find the angular acceleration of bars BC and AB. Homework Equations Relative Motion Equations: v_{b}=v_{A}+v_{A/B}...

Homework Statement A uniform circular disk has radius 35 cm and mass 350 g and its center is at the origin. Then a circular hole of radius 8.75 cm is cut out of it. The center of the hole is a distance 13.125 cm from the center of the disk. Find the moment of inertia of the modified disk...

Homework Statement A uniform circular disk has radius 39 cm and mass 350 g and its center is at the origin. Then a circular hole of radius 9.75 cm is cut out of it. The center of the hole is a distance 14.625 cm from the center of the disk. Find the moment of inertia of the modified disk about...

Hi, i am running a hard disks molecular dynamics simulation. I would like to compare the radial distribution function obtained from my simulation with the theoretical radial distribution function. May i know what is the theoretical radial distribution function? Or what data do people normally...

Hi all, first time here. Huzzah! Looking for help setting up the integral for this: 1. Find the volume of the solid generated by revolving the region bounded by y = x^2 and y = 4x - x^2 around the line y = 6. 2. V = π ʃ [f(x)]^2 dx 3. I've tried every variation of: π ʃ [(x^2 - 6)^2 - (4x -...

Not a homework question per se, but I'm having some issues with moments of inertia. Say I wanted to calculate the I for a ring. What I would do is: I = \int r^2dm m = \lambda L dm = \lambda dL I_{ring} = \int_{0}^{L}\lambda r^2dL And that would give the requiside mr2. My question...

As shown in the figure attached. If both have the magnetization M, what will the B field and H fied for each object look like? why? I have no hint how to answear this question, can anyone help? any reply highly appreciated.

I have 2 P.C.s as follows P.C.1 : 865G/GVM3-V (MS -7101 V2.0) M-ATX MicroStar Motherboard Pentium 4 Dual Core Processor 80 GB WD Hard Disk 1.5 Gb/s 512 MB DDR1 RAM 250 Watt Power Supply Bought in 2006 P.C.2 : M2N68-AM SE2 ASUS Motherboard ATHALON...

In the figure, the cylinder and pulley turn without friction about stationary horizontal axies. A rope of negligible mass is wrapped around the cylinder, passes over the pulley, and has a 3.00-kg box suspended from its free end. There is no slipping between the rope and the pulley surface. The...

Electric charge is distributed over a disk x^2+Y^2<=4 so that the charge density at (x,y) is o(x,y)= x+y+x^2+y^2 what is the total charge on the disk so I change to polar and get (rcos +rsin +r^2)rdrdtheta and my limits go from 0 to 2pi and 0 to 2 for my answer i got 8 pi I am...

In a recent homework problem for my physics class, there was a question regarding a non conducting disk with a charge, and this rotating disk (axis or rotation perpendicular to the surface, through the center) will produce a B field because of the movement of charges. Now suppose I have a...

Homework Statement If Dr is a closed disk of radius r centered at (a,b) find lim r->0 (1/pir2) \int\intfdA over Dr. The Attempt at a Solution From mean value equality, \int\int fdA = f(x,y)A(D) where A(D) is the area of the region which here is pir2. So the lhs becomes lim r->0 f(x,y)...

Hi, I just got of a test that had a question about moment of inertia on it. The question "Calculate the moment of inertia of a thin uniformed disk that is being rotated about an axis of rotation". This axis is halfway between the center of the disk and the outer perimeter. The mass of the disk...

Homework Statement As given in the picture.The Attempt at a Solution So this is what i have done. I calculated: \frac{d\phi}{dt} = B \pi b^2 *\frac{\omega}{2\pi} = e.m.f. R = \frac{\rho a}{at} Thus, I = emf/R = \frac{ar \omega t}{\rho} Sub in I into F = BIL taking L as a. But i...

Homework Statement A computer disk drive is turned on starting from rest and has constant angular acceleration. If it took 0.640s for the drive to make its second complete revolution, how long did it take to make the first complete revolution? Homework Equations...

Homework Statement Uniform time varying magnetic field \vec B_{(t)} pointing at z direction, filling up a circular region on xy-plane. Find the induced E field. I tried two different ways and get two different answers. Please tell me what did I do wrong. Homework Equations Emf...

Homework Statement A solid disk with a radius of 3.3cm is a rest. The disk has 1.0m of string wound on to its circumference. The string is pulled off the disk by a constant force in a time of 4.9s. How many revolutions dose the disk make while the string is being pulled off? Homework...

Homework Statement Let f_n(z)=\sum_{k=0}^n\frac{1}{k!}z^n. Show that for sufficiently large n the polynomial f_n(z) has no roots in D_0(100), i.e. the disk of radius 100 centered at 0. Homework Equations This is a sequence of analytic functions which converges uniformly to e^z on C...

Homework Statement A computer hard drive disk with a diameter of 3.5 inches rotates at 7200 rpm. The “read head” is positioned exactly halfway from the axis of rotation to the outer edge of the disk. What is the tangential speed in m/s of a point on the disk under the read head...

Well, it's my second post about rigid body. I originally posted this on introductory physics, but as nobody answered this, or the previous topic, I've decided to post this here. Homework Statement I have this other exercise rigid in the plane, with which I am having problems. The rod of...

Homework Statement I have this other exercise rigid in the plane, with which I am having problems. The rod of mass m and length l, is released based on the vertical position of rest with the small roller end A resting on the slope. Determine the initial acceleration A. (neglect friction and...

Homework Statement A disk is under constant angular acceleration \alpha. When it starts from rest it takes 10 revolutions before it reaches angular velocity \omega. How many additional revolutions does it take to accelerate the disk further to an angular velocity of 3\omega?The Attempt at a...

I was working on E&M I homework with my friend, and the final question was to find the electric potential at any point on the positive x-axis of a charged disk (where the x-axis is perpendicular to the centre of the disk) We solved this easily enough, starting with a point charge and...

Disk brakes along the rim of the wheel?? Hi friends, I have a doubt. I heard that when we keep the disc brake along the rim of the wheel, less energy is required to stop the wheel. Why is it so?? Why is it not used in today's bikes?:confused:

Homework Statement The potential on the axis of a uniformly charged disk at 4.7 from the disk center is 150 ; the potential 15 from the disk center is 100 . Homework Equations I have no idea what the equations are, I read my textbook looking for equations and I've been searching...

Homework Statement Why is this answer saying that Ea > Eb? Homework Equations Everything pertinent to this question is located in this picture: http://img94.imageshack.us/img94/1187/ch22q9part1.png [PLAIN]http://img94.imageshack.us/img94/1187/ch22q9part1.png The question is...

Homework Statement Disk a and b are identical and roll across a floor with equal speeds. Disk a rolls up an incline, reaching a max height h, and disk B moves up an incline that is identical except that it is frctionless. Is the max height reached by disk b greater than, less than, or equal to...

Homework Statement For each w \in \mathbb{C} define the function \phi_w on the open set \mathbb{C}\backslash \{\bar{w}^{-1}\} by \phi_w (z) = \frac{w - z}{1 - \bar{w}z}, for z \in \mathbb{C}\backslash \{\bar{w}^{-1}\} \back. Prove that \phi_w : \bar{D} \mapsto \bar{D} is a...

Homework Statement an irregularly shaped plastic plate with uniform thickness and density (mass per unit volume) is to be rotated around an axle that is perpendicular to the plate face and through point O. The rotational inertia of the plate about that axle is measured with the following...

Homework Statement A 6kg disk with radius 0.3m initially not spinning. String is wrapped around disk, you pull with constant force of 25N through a distance of 0.6m. What is its angular speed. Homework Equations Krotational=1/2 I w2 The Attempt at a Solution I can't seem to...

Homework Statement A cylindrical disk has volume 8.97 x 10^-3 m^3 and mass 8.16 kg. The disk is floating on the surface on some water with its flat surfaces horizontal. The area of each flat surface is .640 m^2. What is the specific gravity of the disk? How far below the water level is its...

So if we have a supermassive black hole or a regular black hole with gas swirling around it. Can this gas get hot enough to fuse with other gas molecules around it? It seems like there would be enough energy to do this, maybe not. This question seems non-trivial and I think it needs some...

Homework Statement A rotating uniform-density disk of radius 0.7 m is mounted in the vertical plane. The axle is held up by supports that are not shown, and the disk is free to rotate on the nearly frictionless axle. The disk has mass 3.6 kg. A lump of clay with mass 0.4 kg falls and sticks...

Find the volume of the solid obtained by rotating the region bounded by the given curves about the specified line. y= 1 + secx, y=3, about y=1 Set up: 1-1+secx= secx 1-3= -2 A(x)= \pi(secx)^2\,-\,\pi(-2)^2 =\pi(sec^2 x - 4)...

DOS stands for Disk Operating System. Why is it named so? Does the 'system' drive 'disk', or the 'system' is operated using some 'disk'? I know I have it right but it could help you to understand what I'm trying to ask. Please let me know. Thanks.

A disk, cylinder shaped, of mass m and radius r is initially motionless on an ice rink. It has a massless string wound around it which you pull with a constant force F. After your hand has moved a distance d. How far has the c.m. of the disk moved? If someone could show me how I could do this...

Homework Statement The base of a certain solid is an equilateral triangle of side a, with one vertex at the origin and an altitude along the x-axis. Each plane perpendicular to the x-axis intersects the solid in a square cross section with one side in the base of the solid. Find the volume...

A uniform horizontal disk of mass M and radius R is rotating about its vertical axis with an angular velocity \omega. When it is placed on a horizontal surface, the coefficient of kinetic friction between the disk and the surface is \mu_k.Find a)the torque \tau exerted by the force of friction...

A solid sphere with radius r is placed on top of a thin disk with radius R. The contact point is the center of the disk. Both objects are uniform and have the same mass M. Calculate the gravitational potential energy of the system. Take the potential energy to be zero when the sphere and the...

Homework Statement A circular disk of radius R and uniform density is free to pivot about a fixed point P on its circumference. Calculate the period of oscillations of the disk, in the plane of Figure I, when it is displaced by a small angle about its pivot and released. Homework...

Homework Statement Three forces of F1, F2, and F3 are applied to a solid disk with a mass of 3.6 kg and radius of 2.9 meters. F1 is directly above the center of the disk with a magnitude of 47 Newtons directed in the positive x direction, F2 is directly to the right of the center and has a...

I think I did this right but I want to make sure since it is an extra credit problem and I could use the points. If I did something incorrect, I don't want an answer, just point me in the right direction so I can work it out myself. You are designing an auxiliary fuel tank that will fit under...

Homework Statement A disc off a mass m1 is spinning freely at omega1(w1). A second disk of the same radius but smaller mass m2=m1/4 is dropped onto the first , and it sticks. What is the angular velocity of the two disks The Attempt at a Solution I honestly have no idea

Homework Statement A uniform-density 7 kg disk of radius 0.27 m is mounted on a nearly frictionless axle. Initially it is not spinning. A string is wrapped tightly around the disk, and you pull on the string with a constant force of 45 N through a distance of 0.9 m. Now what is the angular...