A hard disk has 63 sectors per track, 10 platters each with 2 recording…

2009

A hard disk has 63 sectors per track, 10 platters each with 2 recording surfaces and 1000 cylinders. The address of a sector is given as a triple (c, h, s), where c is the cylinder number, h is the surface number and s is the sector number. Thus, the 0th sector is addressed as (0, 0, 0), the 1st sector as (0, 0, 1), and so on
The address <400,16,29> corresponds to sector number:

  1. A.

    505035

  2. B.

    505036

  3. C.

    505037

  4. D.

    505038

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Correct answer: C

Formula: sector_number = cylinder × (surfaces × sectors_per_track) + surface × sectors_per_track + sector

  • Number of surfaces = 10 platters × 2 surfaces per platter = 20.

  • Sectors per cylinder = 20 × 63 = 1260.

  • Sectors before cylinder 400 = 400 × 1260 = 504000.

  • Sectors before surface 16 in that cylinder = 16 × 63 = 1008.

  • Add sector offset 29: total = 504000 + 1008 + 29 = 505037.

Therefore, the address <400,16,29> corresponds to linear sector number 505037.

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