Answer: I. 57º 17' II. 1 rad.
Explanation:
A spin speed, implies the relationship between the angle rotated and the time that has been spinning, which is equal, by definition, to the angular velocity.
ω = Δ∅ / Δt
In order to get the angle rotated in degrees, we need to convert first from RPM (revolutions per minute) to º/sec, as follows:
7200 rev/min *( 1 min/60 sec)* (360º/ 1 rev) = 7200* 6= 43200 º/s
Now, we know that the time passed since it started to spin, was 1.326 msec, i.e., 0.001326 sec.
Remembering that ω = Δ∅ / Δt, solving for Δ∅, we get:
Δ∅ = 43200 º /s * 0.001326 sec = 57º 17'
II. In order to get the answer in rads, we can convert the rpm to rads/sec, as follows:
7200 rev/min *( 1 min/60 sec)* (2 π/ 1 rev) = 240 π rad/sec.
Applying the same equation as above, we get:
Δ∅ = 240 π rad/s * 0.001326 sec = 1 rad.
