Question

an audio CD has a diameter of 120 mm and spins at up to 540 rpm. When a CD is spinning at its maximum rate, how much time is required for one revolution? Of a speck of dust rides on the outside edge of the disk,

Answer 1

Answer:

 t = 0.1111 s

Explanation:

Let's reduce the magnitudes to the SI system

    d = 120 mm (1m / 1000 mm)

    d= 0.120 m

    w = 540 rpm (2pi rad / 1 rev) (1 min / 60s)  

     w= 56.55 rad / s

When at maximum speed we can use angular kinematic relationships to find the time for a sperm revolution with zero angular acceleration

     W = θ / t

     t = θ / w

     t = 2π / 56.55

     t = 0.1111 s