A small hard drive typically has only one platter, but each side of it has a magnetic coating. Bigger drives have a series of platters stacked on a central spindle, with a small gap in between them. The platters rotate at up to 10,000 revolutions per minute so the read-write heads can access any part of them.
Answer:
Time taken to travel from one track to the next = 0.08ms
Initial track= 15 0
4 (15-4)*(0.08)= 0.88
40 (40-4)*(0.08)= 2.88
35 (40-35)*(0.08)= 0.4
11 (35-11)*(0.08)= 1.92
14 (14-11)*(0.08)= 0.24
7 (14-7)*(0.08)= 0.56
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Total seek time=0.88+2.88+0.4+1.92+0.24+0.56=6.88ms
Explanation:
We caculate the seek time for each request, and then add them together to find the total seek time. The final track number for the current request becomes the current track of next request, and this process is repeated till the last request is processed.
Answer: A keyframe is a location on a timeline which marks the beginning or end of a transition. So for example, you have a movie and it transitions to another scene, keyframes tell it when and where to start the transition then when and where to stop the transition.
They are replaced by ExpressCard