Question

A disc 8.00cm in radius rotates at a constant rate of 1,200rev/min about its central axis. Determine a). the radial acceleration of a point on the rim and b). the total distance a point on the rim moves in 2.00s

Answer 1

Let
r = radius
ω = angular velocity

"a). the radial acceleration of a point on the rim"
Radial acceleration = rω^2

"b). the total distance a point on the rim moves in 2.00s"
s = rωt

Answer 2

Right.

alternatively, calculate the tangential velocity at the rim from
v = 2 pi R (1200/min)/(60 s/min) v here in cm/s

calculate acceleration from v^2/R

calculate distance moved from v t with t=2.00 s