quote:
Originally posted by Loki^uk
at about 36000 RPM the plastic becomes unstable and therefore could possably eXplode
quote:
Originally posted by traxor
Why wouldn't a cd explode After all it is spinning at a very high speed which not a lot of things could handle, its basically spinning and trying to expand outwards, like you do when you're on the waltzers or whatever, then when the cd is at its highest peak it explodes outwards..
Both wrong actually... The reason why CD's explode (and DVD's, but they spin at a much lower speed so changes are much less of "exploding") is not because they're made out of plastic (and liquifides) or that they can't handle the high velocity. Plastic doesn't become unstable at that speed.
What happens is that the hole in the middle isn't exactly centered (sometimes it only takes a mm at that speed), or that there is an added label or something on the CD. (Also a possible small crack in the surface can cause such things)
This makes that the CD is out of balance. At low speeds this doesn't harm anything, but at high speeds the centrifugal force acts on it and creates a resonance factor. As the speed increases, the force becomes higher and higher and at high speed this makes that there are extremely great forces acting upon the spindle (the thing that goes into the cd-hole) which isn't designed for it. The CD crashes into the drivework and because of it's high speed it breaks (not "explodes")...
That's also the reason why it is strongly adviced not to put selfsticking labels on CD's. It is not because it could damage the surface of the CD, but because the CD would become "out of balance" at high speeds...
quote:
Originally posted by Chaotic_Shield
I had a CD burnt in my CD-RW drive. I guess the CD wasn't made for that high speed. All I smelt was burning plastic and I took the CD out of the drive and is was deformed, extremely hot, and had a huge black mark.
That's something else. The red laser (used for burning the data) proberly malfunctioned and burned your CD (but not in the good sense)...
/ 
