Disk Definition and 819 Threads

A .22kg , .22-m-diameter plastic disk is spun on an axle through its center by an electric motor. What torque must the motor supply to take the disk from 0 to 1500 rpm in 5.00 ? I used the equations T(thau)=alpha/I w_f=w_i + alpha*(t_f - t_i) I found I to be equal to .021kgm^2 then...

Hello. Could anyone give me a hint in this problem? There´s a disk (mass m ad radius a) rotating with angular velocity w0 (only rotation). If this disk is translating in xy plane, parallel with the y-axis with its center aligned at x0, how ca I describe the angular momentum L (t), and it´s...

I'm having some trouble with a conceptual problem. Your help or input would be greatly appreciated. Here's the problem. A disk and a hoop, both having the same mass, are rolled down a hill. The disk rolls faster than the hoop. Why is this so? Thank you for your time!

I have a little problem. There is this message I get, after I direct connect to someone on AIM that says, "The disk in drive A: needs to be reformatted." The options are "Ok" or "Cancel". I clicked "Ok" and the harddrive makes a buzzing sound for quite a while. Why and how do I fix this?

When two pads squeeze a moving rotor with thousands of pounds of force in a disk brake, the friction resists the rotation of the disk enough to slow a car. How much resistance (if any) does the squeezing of the pads provide if you try to pull the moving rotor out at roughly 90 degrees...

I’ve been working on some electroGrav theories and am now wanting to start building models to try and test these theories. I’ve a 8ft satellite dish that I was thinking on using as a mold, but have no good ideas on how to go about this. As like a “UFO”, I need to create a top and bottom...

i am trying to create an animation simulating a coin spinning/rolling on a table top. how can the phyics involved over time be explained in an equation? any references (especially illustrated ones) would be helpful. thanks in advance!

My friend who is working in Seagate told me, the plant is now rolling out high production of 200~400GB HDD. The 40 and 80 GB HDD will phase out soon. Therefore, we will soon see a price drop in HDD. Wait a little bit and you will get higher capacity with cheaper price. :smile:

Right now I'm playing around with DynGen, a routine which uses a hydrodynamical approach to simulate a dusty torus and a planet orbiting within it. It uses laroche limits, etc. to model what happens with the resonant trapping as this planet orbits - the parameters are planet mass and disk...

hoop and disk rolling(help please) ok I've been looking at this forever and can't get it...dont know what to do..i would appreciate it if someone could help -------------------------------------------------------------------------- A uniform solid disk and a uniform hoop are placed side...

if a disk which is initially spinning with an angular velocity,w, radians per second is pushed with an initial linear velocity of v, what is the resultant motion? assume a kinetic friction of mu normal to the disk i would love to see how this problem is solved. it seems real...

I'm not quite getting the following problem: A thin disk of dielectric material, having a total charge +Q uniformly distributed over its surface, and having radius a, rotates n times per second about an axis through the center of the disk and perpendicular to the disk. Show that the...

I've included a picture. A uniform disk of mass Mdisk = 5 kg and radius R = 0.2 m has a small block of mass mblock = 2.5 kg on its rim. It rotates about an axis a distance d = 0.17 m from its center intersecting the disk along the radius on which the block is situated...

[SOLVED] Young's Mod and Spring Constant of a disk Hello, I am trying to find the proper thickness of a disk. In the center of the disk I will attach a steel rod which holds a certain fixed mass. The disk must be a fixed diameter and it can be any reasonable material or thickness. I would...

Hello , Is there any way to get run knoppix from the Hard disk and make it one of the Operating systems to choose ? I hope someone helps me :D

40GB? 60GB? 80GB? Bull****t! I long time ago had found that the hard drive i bought contains less space that what it claims. look at this: Are we cheated by the manufacturers?

http://www.mercola.com/2003/feb/22/petabyte.htm that's 1 million gigabytes, or 1,000 terabytes. Good lord what will we do with it? Ya I can picture going for a walk and listening to my MP3 player with- every song ever written in the palm of my hand. the 24 million texts in the library of...

I am studying for our final, and there is this problem that is confusing me. There are three disks, with transmission axis of the 1st being 10 deg. from the vertical, the 2nd at an angle theta from the vertical, and the 3rd at an angle 120 deg from the vertical. Unpolarized light, I(0) is...

Here's the problem and I'm close to the answer, but I guess close isn't good enough on a Physics exam. A spinning solid disk, rotating with angular velocity Wo, is put down on a level surface. It slides and rolls until it reaches an angular velocity W at which it rolls without sliding. Show...