griffithsuk Posted May 10, 2011 Posted May 10, 2011 (edited) grab yourself a cd case and something like an empty cigrette packet or simular. hold the cd case out close infront of you so its flat and place the cigarette packet on top. If you now spin around correctly the cigarette packet will not fly off however fast you spin. start slowly and no sudden accelarations Why is this? Am i famous now? Griffiths's circle maybe? Edited May 10, 2011 by griffithsuk
Stefan-CoA Posted May 10, 2011 Posted May 10, 2011 No. Sorry, it's the same principle as when you fill a bucket with water and then spin it in a vertical circle. The water won't fall out. It's Newtonian physics. I think. One of the 1st 3 laws I hope.
griffithsuk Posted May 10, 2011 Author Posted May 10, 2011 (edited) No. Sorry, it's the same principle as when you fill a bucket with water and then spin it in a vertical circle. The water won't fall out. It's Newtonian physics. I think. One of the 1st 3 laws I hope. thats different, thats enertia keeping the water in the bucket. mine is free to fly off but it does not if you do it correctly. infact its the opposite, the enertia would make it fly off. do you fell dizzy? Think i have you all here. ive been thinking about this for a week or so now, its just so strange. Another great science party trick! Edited May 10, 2011 by griffithsuk
DevilSolution Posted May 10, 2011 Posted May 10, 2011 thats different, thats enertia keeping the water in the bucket. mine is free to fly off but it does not if you do it correctly. infact its the opposite, the enertia would make it fly off. do you fell dizzy? Think i have you all here. ive been thinking about this for a week or so now, its just so strange. Another great science party trick! Haha, you mean your spinning around the disk? dizzy yet? 1
griffithsuk Posted May 10, 2011 Author Posted May 10, 2011 (edited) Haha, you mean your spinning around the disk? dizzy yet? no, spin around like an ice skater. its the first science dance move Shocking science!Just can't belive it to be true. Anyone any ideas why? Edited May 10, 2011 by griffithsuk
griffithsuk Posted May 11, 2011 Author Posted May 11, 2011 I don't understand, perhaps a diagram? Think your having a laugh back maybe? sorry not got the time
CaptainPanic Posted May 11, 2011 Posted May 11, 2011 What Schrödinger's hat means is that we need a better explanation. What do you do, and what happens?
griffithsuk Posted May 11, 2011 Author Posted May 11, 2011 (edited) What Schrödinger's hat means is that we need a better explanation. What do you do, and what happens? Oh, sorry mate. It's simple hold the cd case out like a drinks tray keeping it flat, put the object on the tray. Spin gently around around like a kid, try so the object does not fly off. once you get good at it you can spin around twice a second and it wont fly off. remember to keep the cd case completly flat. Strange... Edited May 11, 2011 by griffithsuk
Klaynos Posted May 11, 2011 Posted May 11, 2011 If I understand correctly, I think the force you're looking for is friction between the object and cd case. Probably assisted with.slight, probably unconscious tilting of the case.
griffithsuk Posted May 11, 2011 Author Posted May 11, 2011 If I understand correctly, I think the force you're looking for is friction between the object and cd case. Probably assisted with.slight, probably unconscious tilting of the case. im spinning quite fast mate. have a practice with different objects. different weights.
Klaynos Posted May 12, 2011 Posted May 12, 2011 I think a video would help here, or at least photos and a diagram. It's hard to decipher exactly what's going on.
TonyMcC Posted May 12, 2011 Posted May 12, 2011 (edited) It seems to me that the CD case must be tilted so that the object sitting on it doesn't fly off. Perhaps this is done subconsciously. Perhaps one of you mathematicians would like to come up with an angle appropriate to arms length and practical speed of rotation. I wonder if this is some kind of joke where the OP is trying to get as many people feeling giddy as he/she can!? Edited May 12, 2011 by TonyMcC
rktpro Posted May 12, 2011 Posted May 12, 2011 Look, you provide the object initial balance. You move yourself, and keep the case tilted such as it wont fly off at the first spin. It would, no doubt, oppose motion but because of application of force it would move. Both are now considered a single object. Later, due ti inertia, even if you spin twice the speed, it wouldn't fall.
CaptainPanic Posted May 12, 2011 Posted May 12, 2011 So, the CD box and the object on top of it are completely horizontal, and at the center of the rotation, and you run around it at arm's length?
Spyman Posted May 12, 2011 Posted May 12, 2011 I think the OP claims that he is located at the center and the CD casing with cigarette packet on top are spinning around him at arm's length.
CaptainPanic Posted May 12, 2011 Posted May 12, 2011 (edited) I think the OP claims that he is located at the center and the CD casing with cigarette packet on top are spinning around him at arm's length. It is obvious that the OP is withholding some information, deliberately misinforming us about something, or is just joking. We're trying to figure out what's going on. I just posted another suggestion. Maybe he's first dropped a little drop of superglue on the CD box, then placed the object on the glue. Then started spinning, and got dizzy? The OP himself suggested we're dealing with a party trick. Edited May 12, 2011 by CaptainPanic
michel123456 Posted May 12, 2011 Posted May 12, 2011 (edited) If the center of mass of the object is exactly at the center of the CD, it won't fly out. Isn't it? ----------------- edit Griffiths's circle maybe? "Don't disturb my circles". Do you know who said that? Edited May 12, 2011 by michel123456 1
TonyMcC Posted May 12, 2011 Posted May 12, 2011 "Don't disturb my circles". Do you know who said that? Famous last words!
griffithsuk Posted May 13, 2011 Author Posted May 13, 2011 (edited) It's a party trick that works. It won't fly off as long as you don't accelerate more than what the friction keeps it back, other than that you can spin around as fast as you like seriously, im getting good at at. Im either producing gravity, circles are magical things or theres a new type of physical relativity thing going on here? Things relative to each other has some sort of effect? Or something to do with inertia? Something to think about here... It's a party trick like resting one side of a bike wheels spindle on your finger and giving the wheel a spin, it works! Guess I should say a party fact not trick. I think the OP claims that he is located at the center and the CD casing with cigarette packet on top are spinning around him at arm's length. You got it! If your not at arms length it's a bit easyier though as it's not so sensitive. Physical Relativity! I think! Edited May 13, 2011 by griffithsuk
dumber Posted May 15, 2011 Posted May 15, 2011 (edited) It's just friction... There's nothing new here. Yes, it turns out it is just friction, just call m dumb n dumber. Shame though. Anyways my gravity problem arose from how can a moon traveling about 3500mph not fly off when gravity's only over 100mph on earth? If gravity is weaker out in space then that should make it worse. The forces don't seem to work out for me. Anyone answer this? Edited May 15, 2011 by dumber
Klaynos Posted May 16, 2011 Posted May 16, 2011 Moons orbit can quite easily be understood by newtonian gravity. http://en.wikipedia.org/wiki/Newton%27s_law_of_universal_gravitation I am however puzzled by the phrase "gravity's only over 100mph on earth?" The speed of gravity is the same as the speed of light so I'm not sure what that means.
CaptainPanic Posted May 17, 2011 Posted May 17, 2011 Maybe he means the terminal velocity of a human when he says the speed of gravity? Gravity is not a speed, it's an acceleration, expressed in m/s2.
swansont Posted May 17, 2011 Posted May 17, 2011 ! Moderator Note FYI griffithsuk/dumber are sockpuppets of infinitesolid and gafferuk, et. al, who has previously posted serious and persistent misunderstandings of gravity with no improvement in comprehension. The sockpuppets have been banned.Nothing more to see here.
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