Knowledge of OcUk unite!

[Burnsy2023]

Back on topic, it depends whether the question is asking about sustained read speeds or seek times. I would assume it's a seek time issue, in which case the fact that an optical disc spins slower and the laser takes longer to get into position would be the primary factors.

 

[VFM Addict]

"Explain why it takes longer to access data in an optical disk than in a magnetic disk."

Because most of the time you can't remember where you left the 'kin CD/DVD.

Obvious really.

 

[Dave M]

I don't think a DVD spins slower than a hard drive but data density is awful in comparison to any hard drive.

I'd guess locating a particular bit is much harder on a CD as with the best will in the world it's not in exactly the same position (relative to the read head) as last time it was put in.

 

[Vonhelmet]

I don't think a DVD spins slower than a hard drive but data density is awful in comparison to any hard drive.

Audio CD players read their discs at a constant 150 kB/s and thus must vary the disc's rotational speed from around 500 rpm (actually 8 Hz), when reading at the innermost edge, to 200 rpm (actually 3.5 Hz) at the outer edge. CD-ROM drives’ maximum rotational speeds are rated in multiples of this figure, even though they do not hold to constant read speeds when reading from most disc formats.

So a 48x CD drive (did they ever make any faster than that?) would theoretically rotate at 24,000rpm to 9,600rpm but with much lower data density.

DVD players also usually read discs at a constant linear rate. The disc's rotational speed varies from 1530 rpm (actually 25.5 Hz), when reading at the innermost edge, and 630 rpm (actually 10.5 Hz) at the outer edge. DVD drives’ speeds are usually given in multiples of this figure.

So a 16x DVD drive rotates at 24,480rpm to 10,080rpm.

So, both CDs and DVDs should be as fast as hard disks, but data density is much lower.

Note that this assumes that the 48x or 16x or whatever applies to rotation rates whether reading from the inner or outer edge of the disc, which is almost certainly not the case, as I very much doubt a DVD could withstand being rotated at 25,000 rpm.

 

[cm1179]

i can only imagine what other questions came up

'where is a girls vagina'?

 

[PhillyDee]

I did have an x52 speed drive. and from what I can see, there was an x72 drive. They were not very reliable though!

 

[Trusty]

i can only imagine what other questions came up

'where is a girls vagina'?

Lol. Is this it?

*points to a girls ear*

 

[s0ck]

lol