Disc Definition and 374 Threads

Why has this not coalesced yet to form a planet?

A bullet of mass m hits a disc of radius R on its periphery at speed v.What will be the velocity of disc if the collision is inelastic?

Rotating Disc & Speed of Light ?! If a point on a disc's outer edge is traveling close to the speed of light and things contract in the direction of the acceleration at those speeds (relative to a stationary observer) would that mean the disc's radius stays the same but the circumfrance...

Oh since this got moved: It's not for any course or class so I'm not following any book. I'm not sure if anyone will be able to answer this but I'll ask anyway: I've solved laplaces equation in cyclindrical coordinates for a disc of radius 'a' and constant potential V on the disk (disc in z=0...

Hey guys, so I'm back in school after an 8-month break, and I'm feeling a bit rusty :rolleyes: So I've got a flat disc of radius A, with constant density p, in the z=0 plane. I want to calculate the gravitational field at any point up or down the z-axis. I integrated the potential over the...

I'm doing a project on accretion disks, and I was wondering if anyone could suggest something interesting relating to their observation that I could talk about. One thing I remember reading was that accretion discs are one of the most compelling means of proving the existence of black holes...

Hello All! I have one machine. The disc (Horizontal place) is rotating and connecting to the shaft which is connecting to gear box and ac motor. I would like to k now the torque of rotating disc for some interval such as 10s, 20s, 30s, to take reading , but I do not have money to buy...

A disc of moment of inertia 29.1 kg m2 is made to rotate about an axis through its centre by a torque of T . The disc starts from rest and, after {t} s, has kinetic energy {k} J. The torque is removed when the disc is rotating at 8.0 rad s-1 . An opposing torque of 13.2 N m is applied to slow...

moment on a circular disc(moment applied in the centre) A circular disc is hinged in the centre. I am applying a moment at the centre. The result is that the disc will rotate with an angular acceleration "a" moment on a circular disc(moment applied not in the centre) A circular...

Electric field of Charged disc Find the electric field at a distance 'z' above a uniformly charged disk of radius R. I have solved this problem. Can someone just clarify if my solution is right? I couldn't attach a diagram..sorry! Solution: Using conventional notations, \sigma is the...

i have a rotating disc. I have a tachometer and a sensor tape. Where should i stick the tape to measure the rpm correctly? How tachometer works? One more question. a rotating disc has kinetic energy. Why we study energy of a rotating. Now if i stop the rotating disc according to law of...

A thin string has been wound around a homogenous circular disc A in such a way that the disc can oroll on a horiz0ontal surface. The mass of the disc is M and its radius is R. The string goes around a small frictionless pulley C at a height 2Rabove the horizontal table B. To the free end of teh...

A few minutes ago, I had a CD in my computer which I was listening to. I switched the CD for another one, and it didn't recognize that CD. I tried 4 other CD's, and my computer keeps showing a little icon oc a CD next to my mouse right when the CD is put in, but then acts as if there's no CD in...

I'm stuck on a miniquestion in my HW that is hindering the entire problem, so here it is. A disc of mass M, radius R, Icm =1/2MR^2 is rolling down an incline dragging a mass M attached with a light rod to a bearing at the center of the disc. The friction coefficients are the same for both...

What do the strange values on disc capacitors signify exa 005 and 5D 1KV , why can't they just be abbreviated in a more intuative way like for exa just 10 micro farads ? Also for a small mic how can I tell apart which ends which + or 1 and what do the letters HAI signify on some...

Two frictionless discs on air table, initially at rest, are driven apart by an explosion with velocities of 9.0m/s and 5.0m/s what is ratio of masses? how do i get masses if i don't know Momentum ? +__+

Problem: The coefficient of kinetic friction between the 100 lb disk and the surface of the conveyor belt is 0.2. If the conveyor belt is moving with a speed of 6 ft/s when the disk is placed in contact with it determine the number of revolutions the disk makes before it reaches a constant...

I want to put some permanent ink on disc golf discs, i don't know if any of you are familiar with these frisbee type discs... I was wondering what the best kinds of ink to use are and how to apply the ink to the disc so that it does not run. i have no experience in this type of work so it's...

If I have a solid disc with a diameter of 30 cm and a mass of 700 grams with a speed of 45 rpm, and a mass of 350 grams falls 6 cm from center what is the speed of the disc. There are also no external torques. I have no problem solving the angular momentum of the disc before the mass falls...

What if we had a large and massive object shaped like a disc (look at the attachment) and we would walk on its edge. If we would step on the flat part what would happen? P.S. I am going on holidays for a fe days so i won't be abel to check out your answers very soon.

I think I'm starting to abuse this forum. Anyways, it seems that I haven't grasped the concept of angular acceleration yet since I'm having trouble solving this problem: Suppose I have a disc laying on the x-y plane with center at the origin. Suppose the disc is rotating about the z-axis with...

A question, I have a plastic disc with a coil wound around is axis of rotation. The coil carries current I. Now the disc carries charges at its circumference. Now the current flowing in the coil is brought to 0 instantaneously. This creates Electric Field to be produced that travel in...

Famous Hoover "disc" quote debunked: Ivan Seeking On television and in most of the current Roswell literature, this quote is often cited as evidence that Hoover had a continuing interest in the Roswell disc and the "other discs recovered". Here, thanks to some skeptical prodding by Zoobyshoe...

My friend just bought a mini disc player, and apparently it uses an optical cable to connect to a computer. I think I know what an optical cable is, but I've never heard of an optical port, and I've never seen one on a comp before. Are they a fairly recent development, or am I just blind?