Why do hard disks/CD’s have to spin fast

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Can we write the data as a single track, that way they could spin very slowly, like a vinly record.

Thanks.

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Anonymous 0 Comments

Compact discs ARE a single track, a spiral that goes from the inside out. An audio disc does spin relatively slowly, 200RPM-500RPM, but they spin at that rate much higher than LP because the sample rate and encoding of CD requires about 3 million bit transitions between “pit” and “land” per second to play digital audio. Were they to use newer Blu-Ray technology with much smaller bits, they could spin slower.

A hard drive instead requires access to data on-demand. Understand that the data is already packed as densely as the present technology allows. Slowing the rotation speed would impact performance in two ways:

-The amount of data passing under the read head would slow, increasing the transfer time.

-The amount of time that you have to wait for the correct data position to rotate around to underneath the head increases (latency)

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