edited by
532 views
1 votes
1 votes

A hard disk system has the following parameters:

  • Rotation speed – $6000$ rpm.
  • Size of each sector – $1$ KB.
  • Average number of sectors per track – $128$.

Based on these parameters, which of the following statements is/are CORRECT? 

  1. The average latency of the drive is less than $6$ milliseconds.
  2. The burst data rate of the drive is more than $10$ MB/sec.
  3. The average capacity per track is larger than $1$ MB.
  1. I only
  2. I and III only
  3. I and II only
  4. I, II, and III
edited by

1 Answer

Best answer
2 votes
2 votes
1. Average rotational latency in hard drive is

(1 / (RPM / 60)) * 0.5 * 1000  ms

Or, (30000 / RPM)  ms = 30000 / 6000 = 5 ms , this makes statement I correct .

2. The burst data rate is  average track capacity * rotations per second = 128 * 0.001 * 100 MB/sec = 12.5 MB per second ( as 1 KB = 0.001 MB ) , this makes statement II correct.

3. The average capacity of each track is average number of sectors per track *  the size per sector = (128 * 1) KB =128 KB, which makes statement III false .

So, only statement I and II are correct , which is option C .
Answer:

Related questions

428
views
3 answers
1 votes
Bikram asked Nov 25, 2016
428 views
Consider the following program segment for a CPU having three Registers $R1, R2,$ and $R3$ ... being executing by the CPU, then the return address saved onto the stack will be _______.
462
views
1 answers
1 votes
Bikram asked Nov 25, 2016
462 views
A CPU has a $32$ KB direct-mapped cache with $128$byte block size. $'A'$ is a two dimensional array of size $512 \times 512$ with elements that occupy $8$bytes each.for ( ... $2^{14}$2^{18}$2^{15}$
514
views
1 answers
1 votes
Bikram asked Nov 25, 2016
514 views
A computer system has a main memory consisting of $1$M $16$-bit words. It also has a $4$K-word cache organized in the block-set-associative manner (with $4$ blocks ... $3.16$2.15$2.19$
301
views
1 answers
0 votes
Bikram asked Nov 25, 2016
301 views
The memory unit of a computer has $256$ K words of $32$ bits each. The computer has an instruction format with four fields: an operation code field, a mode field (to specify one of ... $5,6,3,18$5,18,6,3$5,3,6,18$