## Invitation to Computer Science 8th Edition

The new rotational speed is $7,200$ rev/min $=120 \mathrm{rev} / \mathrm{sec}=8.33$ msec/rev. The seek time is unaffected by the rotational speed. The new average latency time is 0.5 rev $\times 8.33$ msec/rev $=4.17$ msec. The new transfer time is 1$/ 20$ rev $\times 8.33$ msec/rev $=0.42$ msec. The total average case time $=12.59$ msec.
The new rotational speed is $7,200$ rev/min $=120 \mathrm{rev} / \mathrm{sec}=8.33$ msec/rev. The seek time is unaffected by the rotational speed. The new average latency time is 0.5 rev $\times 8.33$ msec/rev $=4.17$ msec. The new transfer time is 1$/ 20$ rev $\times 8.33$ msec/rev $=0.42$ msec. The total average case time $=12.59$ msec.