Figured out that if you simply add the entry and put value to 1, you will have a time varying writing speed , which is the actual speed.
This because we know that most recorders write at CAV (constant angular velocity) mode hence as the laserlens bed moves from the interior to the exterior the radius R is increasing and the recording speed is:
linear velocity=angular velocity(constant)*R(time varying)
is time varying(more specifically it increases as radius does also) also.
Am i smart or what?