1. R

    Solid Disk

    Hello all Any help to solve these two problems? i will be so thankful. Best regards
  2. R

    Rolling Disk

    Greetings to all Any help please to solve these two problems? i will be so thankful . Best regards
  3. K

    Am I doomed to never understand the relativistic rotating disk?

    Ok, I am really out of my depth here so I am wondering whether I can get any mileage with this with just flat minkowski space with uniformly rotating polar co-ordinates and some vector calculus and linear algebra? (I'm really not good with tensors). Is it worth me trying to understand some...
  4. P

    Help with Past Exam Question on Rolling Disk on Hemisphere

    Hoping to outdo his physics professor, Doofus wants to dramatically demonstrate parabolic motion by throwing a cheese wheel of mass m and radius r off of the top of the UW observatory, which is at a height 3R above the roof of the physics building, as shown in the diagram. Just as he is...
  5. S

    Electric field at center of a disk

    We've just begun electrostatics in school. I can't seem to understand why the field at the center of a uniform charged disk is not equal to zero. We found the formula for its field by assuming the disk to be made up of charged rings and then integrating it. The field at the center of a ring is...
  6. M

    lump disk mass to a point

    hello imagine a disk rotating by an axis that passes through the center of the disk how can we find the analogue of a mass rotating by an axis? I mean, how can we lump the whole mass of the wheel to a point? how much will be the distance of this point from the axis? for example to...
  7. L

    Electric Field Magnitude of a Disk

    A uniformly charged plastic disk has a radius of 0.220 m. At what distance from the center along the central perpendicular axis is the magnitude of the electric field equal to one-half the magnitude of the field at the center of the surface of the disk? I don't know how to find the magnitude at...
  8. H

    angular velocity of a disk

    Could someone give me some tips on how to get started with this? I don't know what to do. A force of 18 N is applied to a disk of mass 2.4 kg at a distance of R = 7.0 cm from its center. What is the angular velocity of the disk after 5.0 sec? Do I need to find the rotational inertia of the...
  9. T

    [SOLVED] Velocity of ring, disk, and sphere down incline?

    In an upcoming physics test, one of the problems is to find the velocity of a ring, disk, and sphere of unknown masses and radii down an incline of unknown length and angle. The specific instruction is to find what coefficient of gh under a radical equals the velocity of each, or V = sqrt(_gh)...
  10. F

    disk making contact with a convayor

    First, this is the pic: http://img60.imageshack.us/img60/7782/question6jh6.png The axis of a disk with radius of 0.05m is fitted into a slot that forms an angle of 30degs with the vertical axis. The disk is at rest when it is placed in contact with a conveyor belt moving at constant speed. The...