Hawaii Linux Institute wrote:
BTW, I did a wrong calculation in the linear speed of a hard disc. It should be about 40 miles per hours, and definitely not 10,000 miles per hour.
But keep in mind that the separation between the magnetic head (which is stationary) and the disc surface (which is spinning at about 40 MPH) is less than 20 Angstroms. Basically, this separation is filled with two or at most three layers of lubricating molecules. These lubricating molecules, which are mobile, can disappear due to heat dissipation, pressure gradients, or whatever reason(s).
Wayne
