Question

A computer is reading data from a rotating cd-rom. at a point that is 0.0130 m from the center of the disk, the centripetal acceleration is 393 m/s2. what is the centripetal acceleration at a point that is 0.0884 m from the center of the disc?

Answer 1

The formula relating acceleration and angular velocity is:

a = ω^2 r

where a is acceleration, ω is angular velocity and r is radius

But the angular velocity ω is constant all throughout the disk therefore:

a1 / r1 = a2 / r2

 

So at points:

r1 = 0.0130 m     -> a1 = 393 m/s^2

r2 = 0.0884 m     -> a2 = ?

 

393 / 0.0130 = a2 / 0.0884

a2 = 2,672.4 m/s^2