Question

As an audio CD plays, the frequency at which the disk spins changes.

At 210 rpm, the speed of a point on the outside edge of the disk is 1.3 m/s.

At 420 rpm, the speed of a point on the outside edge is ___ m/s.

Answer 1

The velocity is 2.5997 m/s.

Step-by-step explanation:

The given condition :-

1) N = 210 rpm

speed ( v ) = 1.3 m/s.

We know that ,

v = r ω

where r = radius of disk.

ω = angular velocity.

But ω =
`(2*\pi*N )/(60)`

`v = (r* 2*\pi*210 )/(60)`

`1.3 = (r*2*\pi*210 )/(60)`

r = 0.059144 m

2) N = 420 rpm

`v = (r* 2*\pi*N )/(60)`
`= (0.059144*2*3.14*420)/(60)`

v = 2.5997 m/s.

So we get the velocity v = 2.5997 m/s.