- With Constant Linear Velocity, CLV, the density of bits is uniform from cylinder to cylinder. Because there are more sectors in outer cylinders, the disk spins slower when reading those cylinders, causing the rate of bits passing under the read-write head to remain constant. This is the approach used by modern CDs and DVDs.
- With Constant Angular Velocity, CAV, the disk rotates at a constant angular speed, with the bit density decreasing on outer cylinders. ( These disks would have a constant number of sectors per track on all cylinders. )
- CLV$=10+20+30+40+..80=360$
- CAV$=10\times8 = 80$ so answer should be (D)
Edit:- for CLV disk capacity
let track diameters like $1$cm, $2$cm... $8$cm.
As described that density is uniform.
So all tracks has equal storage density.
Track capacity$=$storage density $\times$ circumference$(2 \times pi \times r)$
For $1$st track. $10 \text{MB} = \text{density} \times 2 \times pi \times 1$
Density $= 10/pi.$ MB/cm
For $2$nd track capacity = density $\times$ circumference
$= (10/pi) \times(pi \times 2) \text{MB} = 20 \text{MB}$
Now each track capacity can be calculated and added for disk capacity