Disk Definition and 819 Threads

The Confederation of Revolutionary Trade Unions of Turkey (Turkish: Türkiye Devrimci İşçi Sendikaları Konfederasyonu, DİSK) is one of the four major national trade union centres in Turkey. It was founded in 1967 as a breakaway union from the Confederation of Turkish Trade Unions, and has a membership of 327,000.
DİSK is affiliated with the International Trade Union Confederation, World Federation of Trade Unions, Trade Union Advisory Committee to the OECD and the European Trade Union Confederation.

View More On Wikipedia.org
Recent contents Top users
  1. J

    Find E, circular disk. Radial component of E question.

    Hi, I'm not sure this falls under the homework category, but I posted this here because I think this is more of an insight question than a question for help on how to solve the excercise (which I have). I am reading Sadiku's Elements of Electromagnetism. There is an exercise reads something...
  2. F

    Rotating disk with friction on the boundary

    Hi everybody! I'm having some problem with the following system... I have a 2D problem, a disk is rotating with constant velocity, but there is a friction on the boundary due to the contact between the disk and the surrounding material. I'd like to find the analytical formula of the...
  3. K

    Why is my computer showing inconsistent free disk space readings?

    I just picked up an older computer (Dell with XP) to substitute for and eventually augment a machine that has turned boat-anchor on me (I'll get to that one at a later date). The main problem is the readings I get from "my computer" of the remaining "free space". Sometimes it reads as low as a...
  4. L

    Wavefunction for particle inside a disk

    I am trying to solve for the wavefunction for a particle inside a 2 dimensional disk of radius r_0. The conditions are: \int^{2\pi}_0 \int^{r_0}_0 |\psi|^2\, r \,dr\, d\theta = 1 Then I tried separations of variables (set psi = R(r)Theta(theta)) to solve the Schrodinger equattion. didnt'...
  5. P

    Solving Volume with the Disk Method: Graph & Tips

    http://www.webassign.net/www14/symImages/5/5/e52c6d3f5c64e9f5bf52f9a215f4f2.gif V = (pi)(r^2) I tried to graph this but it seemed like the graph kept going. what do i do?
  6. S

    Find period of circular disk physical pendulum

    Homework Statement A uniform circular disk whose radius R is 40.0 cm is suspended as a physical pendulum from a point on its rim. (a) What is its period of oscillation? (b) At what radial distance r < R is there a point of suspension that gives the same period? R = .40 m g = 9.81...
  7. F

    Quick question on disk defragmentation

    I'm at the library, and while studying for my last final, I am running disk defragmenter on my laptop. It has been running for a little over 3 hours now and the library closes in 20 minutes. If it is not finished by the time the library closes, will I have to wait another 3+ hourswhen I get...
  8. K

    Torque about the axle of a rotating disk

    Homework Statement "The 19.8 cm diameter disk rotates on an axle through its center. F1=18.1 N, F2=26.6 N, F3=26.6 N, F4=18.1 N, and d=4.64 cm. What is the net torque about the axle? " http://i4.photobucket.com/albums/y111/kathy_felldown/kn-pic1314.png I have two questions about this...
  9. D

    Magnetic field of revolving disk

    find the expression for the magnetic field at a distance z on the axis which passes through the centre of a disk, with a radius of R, and a charge density σ, the disk is rotating at an anular velocity of ω...
  10. S

    Centripetal Acceleration circular disk

    Homework Statement A circular disk of radius 30 cm is rotating with an angular acceleration of 1 radian/ s2. What is the tangential acceleration of a point on the rim of the disk? What is its centripetal acceleration if the angular speed is 3 rev / s? Homework Equations tangential...
  11. A

    Faradays rotating disk paradox

    Hello, I was reading about Faradays rotating disk paradox wherein when both the copper disk and magnet are rotated together an eddy current is induced along the radius of the copper disk. My question is if a maganitized steel disk (with one side being the N pole and the other side...
  12. L

    Seagate ST3750640AS 750GB: Maximum Data Flow and Outer Zone Sectors Calculation

    Hi, This is probably a simple question, but not for me. Seagate ST3750640AS 750GB can provide maximum data flow from disk 624 Mbit/s. How many sectors are in outer zone tracks if average rotation latency is 4.16ms? I've no idea how to calculete this
  13. C

    What is the velocity and kinetic energy of a rolling disk on an inclined plane?

    Homework Statement A solid disk of mass m = 2.2 kg and radius r = .20 m starts from rest at a height h = 3.2 m and rolls without slipping down an incline plane with an angle of 30 degrees above the horizontal. a What is the linear velocity of the disk at the bottom of the incline...
  14. C

    Calculating Angular Acceleration, Torque, and Work on a Solid Disk

    Homework Statement A solid disk starts from rest and is accelerated to 25 rad/s in 12 sec. The mass of the disk is 4 kg and the radius is 0.15 m. What was the angular acceleration of the disk? What torque was needed to do this? How much work was done on the disk in this time? Homework...
  15. P

    How to Calculate Forces Leading to Disk Failure?

    I would like to be able to calculate the forces on a spinning disk to determine the rpm it will fly apart given its dimensions and the mechanical properties of the material it's made of. I understand centripital and centrifugal forces. However, I'm not understanding how I to set up the problem...
  16. M

    Why electic potential on the center of a disk axis = 0

    when i saw how to get the electic potential of a charged disk at a point on its axis i found that the E.P on center of the disk =0 as the integration of the eq: dv = 2k(q/a^2)((r^2)+(x^2))^(.5)dr...(a) is the radius of the disk , (r) is the radius of the element and (x) is the distance...
  17. E

    Flux Calculation for Disk Geometry

    Homework Statement http://img13.imageshack.us/img13/88/fluxm.th.jpg Homework Equations The Attempt at a Solution I am having difficulties to work this problem out. I know the formula is : http://img13.imageshack.us/img13/4883/formmix.th.jpg
  18. V

    Rolling disk with point mass on edge

    Homework Statement A point mass m is attached to the rim of an otherwise uniform solid disk of mass M and radius R (in the diagram mass m is in contact with the ground). The disk is rolled slightly away from its equilibrium position and released. It rolls back and forth without slipping...
  19. E

    Capacitance from a separated plate disk

    Homework Statement Ok, let's say that I have two plate disk, with an area of A and they are separated with a distance d apart from each other. I need to measure the half-life of exponential decay to calculate capacitance. I need to graph C vs x = 1/d, however how can I get C ?? Homework...
  20. F

    How Do You Calculate the Torque on a Spinning Disk?

    spinning disk torque? Homework Statement A uniform solid disk with radius 10 cm has mass 0.7 kg (moment of inertia I = ½MR2). A constant force 12 N is applied as shown. At the instant shown, the angular velocity of the disk is 40 radians/s in the -z direction (where +x is to the right, +y...
  21. M

    Spinning disk revolutions homework

    Spinning Disk A disk with a diameter of 0.06 m is spinning with a constant velocity 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 15 g's...
  22. K

    How fast does the disk move when pulled by a string?

    [b]1. 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. (A) When the disk has moved a distance of 3.2 m...
  23. M

    The fundamental group of the disk is trivial, why?

    How do we show that the fundamental group of the disk D^2={(x,y) in RxR: x^2 +y^2< or eq. to 1} is trivial? I know how to show that the fundamental group of the circle is isomorphic to the group of the integers under addition, but for some reason, I don't see a way to show that the...
  24. D

    Find Flux through a Disk in Electrostatics Question

    in this electrostatics question i have a disk with a radius of R, and i have a charge q placed at a distance of R/2 perpendicular to the disk from its centre. i am asked to find the flux through the disk WHAT I DID:-- here are my calculations and i diagram...
  25. N

    Disk Rotating Near the Speed of Light

    I was sitting in Physics class today while we were talking about the speed of light. I know almost every physicist will say that nothing can go faster than the speed of light. While all of these men and women know more than me, one thing they fail to realize is that every single time anyone says...
  26. D

    Find the number of bits that can be stored on a 10cm disk

    Homework Statement A computer disk is made by focusing light to a spot whose diameter is comparable to the optical wavelength. Find the number of bits that can be stored on a 10cm diameter optical disk using an infrared laser. Homework Equations Lamda λ = diametre of laser The...
  27. G

    How does a disk roll down an incline?

    A uniform disk of mass m and radius R rolls without slipping down a ramp inclined at angle q to the horizontal. Using the angle f through which it turns as a generalised coordinate, write the lagrangian, and then the Hamiltonian. Write out and solve Hamilton’s equations of motion. Ok, so...
  28. M

    How Do You Calculate Angular Acceleration from Tangential Acceleration?

    Disk rotating problem. urgent, help pls.. Homework Statement A disk of radius 30.0cm 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...
  29. D

    What is the Electric Flux Through a Disk with a Charge at 0.5R?

    what is the electric flux through a disk with a radius R when a charge of q is placed at a distance of 0.5R perpendicular to the centre of the disk ?
  30. D

    A mass attached to a cord around a disk

    Homework Statement Imagine a frictionless pulley (a solid cylinder) of unknown mass M and radius r = 0.200 m which is used to draw water from a well. A bucket of mass m = 1.50 kg is attached to a massless cord wrapped around the pulley. The bucket starts from rest at the top of the well and...
  31. P

    Lagrange equation problem involving disk

    Homework Statement A uniform disk of mass M and radius a can roll along a rough horizontal rail. A particle of mass m is suspended from the center C of the disk by a light inextensible string b. The whole system moves in a vertical plane through a rail. Take as generalized coordinates x...
  32. T

    Disk and Block (Moment of Inertia)

    Homework Statement A uniform disk of mass Mdisk = 4.1 kg and radius R = 0.3 m has a small block of mass mblock = 2.9 kg on its rim. It rotates about an axis a distance d = 0.16 m from its center intersecting the disk along the radius on which the block is situated. a) What is the moment of...
  33. T

    Spinning Disk (circular motion)

    Homework Statement A disk with a diameter of 0.07 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 g's (i.e., 14 times the...
  34. E

    It is a good question about disk method Can you help me to solve

    Disk method question Use the disk method to find the volume of the solid obtained by rotating the region bounded by y=x^2 and y=x about the line y=x.
  35. O

    How to run an iso off of restart without burning to disk

    I currently have an iso of a program inwhich I would like to install on my home desktop. However my home desktop only has a cd-rom drive and not a dvd room drive so I can't burn it to the disk. I know I can still mount and run it using a program such as daemontools however I don't know of a way...
  36. B

    What is the Potential of a Charged Disk?

    I've attached a .pdf with the problem explanation, questions, and answers. I can't figure out for the life of me how to get these answers though. I've setup a countless number of integrals and can't seem to get it right. Any help you guys can give me would be greatly appreciated. *EDIT* Not...
  37. N

    How Many Zeros Are Inside the Unit Disk for f(z) = 3z^621 - e^z?

    How many zeros inside the unit disk does the following function have? f(z) = 3 z^621 - e^z. (in words, three times z to the power 621 minus e^z :) ...argument principle answers this question, but I have a problem evaluating the integral of f'(z)/f(z).
  38. pellman

    How does a hemisphere differ from a disk?

    Can the surface of a hemisphere be distinguished from a disk without introducing a metric? What is the minimum amount of info we need to know to identify one space as a disk and the other as the surface of hemisphere? Both can have the same coordinate chart. For example, distance from...
  39. G

    Using disk method with respect to y-axis

    Homework Statement y=\sqrt{x}, x=4, y=0 Homework Equations \pi\int^{c}_{d}{R(y)}^{2}dy The Attempt at a Solution I solve for x then pluged it into the formula \int^{2}_{0}{(y^{2})^{2}} The answer I got was \frac{32\pi}{5} but my textbook says the answer should be...
  40. B

    The Electric Field Due to a Charged Disk

    Homework Statement A circular plastic disk with radius R = 1.80 cm has a uniformly distributed charge of Q = + 2.15 106 e on one face. A circular ring of width 30 µm is centered on that face, with the center of the ring at radius r = 0.50 cm. What charge is contained within the width of the...
  41. J

    Electric Field Due to a Charged Disk

    Homework Statement Suppose you design an apparatus in which a uniformly charged disk of radius R is to produce an electric field. The field magnitude is most important along the central perpendicular axis of the disk, at a point P at distance 2.60R from the disk. Cost analysis suggests that...
  42. S

    Disk on a Plank Acceleration and Displacement Calculations

    disk on a plank -- HELP! Homework Statement a disk of mass M is sitting on a plank of length l and mass m. a constant force F is pulling the plank to the right. assuming no slipping what are the accelerations? how far to the right will the coin move before reaching the left end of the...
  43. M

    Optimizing Wetted Area in a Rotating Disk Evaporator

    A circular disk of radius r is used in an evaporator and is rotated in a vertical plane. It is to be partially submerged in the liquid so as to maximize the exposed wetted area of the disk. show that the center of the disk should be positioned at height r/sqrt(1+pi^2) ok i absolutely know how...
  44. Q

    Uniform disk lying on a flat, frictionless surface

    A uniform disk is lying on a flat, frictionless surface, and a force is applied as shown: http://www.freeimagehosting.net/uploads/ae622047b5.jpg What will be the motion of the disk.. more importantly, the motion of center of mass of the disk. will it move in a straight line, or will it move...
  45. P

    Integrating a Vector Field Over a Circular Disk

    Hi, How do integrate this? I wish to see it step by step and I'm glad for any help i can get. \int_{ \vec{r}\in{A}} \frac{ \vec{v}+ \vec{\omega}\times\vec{r}}{| \vec{v}+ \vec{\omega}\times\vec{r}|}d^{2}r where A is area of disk with radius R.
  46. L

    A disk with a Spring around it

    Homework Statement A string is wrapped around a uniform disk of mass M = 2.5 kg and radius R = 0.05 m. (Recall that the moment of inertia of a uniform disk is (1/2)MR2.) Attached to the disk are four low-mass rods of radius b = 0.09 m, each with a small mass m = 0.7 kg at the end. The device...
  47. N

    Angular Momentum: Rod on Rotating Disk

    Homework Statement A uniform disk (like a record turntable) turns with a frequency of 5.2 rev/s around a frictionless spindle. A non-rotating rod of the same mass as the disk and length equal to the disk's diameter is placed on the freely spinning disk so both turn around the spindle. (Idisk...
  48. M

    Angular Speed of Rotating Disk: Omega Final & Initial

    Homework Statement A uniform disk is set into rotation with an initial angular speed about its axis through its center. While still rotating at this speed, the disk is placed in contact with a horizontal surface and released. What is the angular speed of the disk once pure rolling takes place...
  49. C

    What Torque is Needed to Spin a 250g Disk to 2000 RPM in 4.5 Seconds?

    Homework Statement A 250 g , 20.0-cm-diameter plastic disk is spun on an axle through its center by an electric motor. Homework Equations What torque must the motor supply to take the disk from 0 to 2000 rpm in 4.50 s? The Attempt at a Solution I know that Torque = Inertia times angular...
  50. O

    Moment of inertia - disk - finding dm

    Comments ---------- hey, I am trying to figure out the moment of inertia with respect to various axis. I am, having trouble figuring out how to find out dm. I know that dm = (rho)*t*dA, but i am having trouble figuring out the t*dA part. i tried using t*dA = (pi)(r^2)/2 That didn't...
Back
Top