Question

the platter of a computer hard drive disk rotates 5400 rpm. a) What is the angular velocity of the disk? b) If the reading head of the drive is located 3.0 cm from the rotational axis, what is the speed of the disk below it? c) What is the linear acceleration of this point? d) If a single bit requires 5um of length along the motion direction, how many bits/seconds can the writing head write when it is 3.0 cm from the axis?

Answer 1

w-angular velocity of the disk=*2pi=180pi

If the reading head of the drive is located 3.0 cm from the rotational axis, what is the speed of the disk below it?

V=wR=3*180pi=540pi

What is the linear acceleration of this point?

It is 0

d) If a single bit requires 5um of length along the motion direction, how many bits/seconds can the writing head write when it is 3.0 cm from the axis?

5*n=540pi

n- bits

n=108*pi bits per second