Answer:
α = 5.5π rad/s² ≈ 17.3 rad/s²
Explanation:
The angular acceleration is the change in angular velocity over time. First, we need to convert revolutions per minute to radians per second.
The initial angular velocity is:
ω₀ = 1200 rev/min × (2π rad/rev) × (1 min / 60 s) = 40π rad/s
The final angular velocity is:
ω = 4500 rev/min × (2π rad/rev) × (1 min / 60 s) = 150π rad/s
The angular acceleration is:
α = (ω − ω₀) / t
α = (150π rad/s − 40π rad/s) / (20 s)
α = 5.5π rad/s²
α ≈ 17.3 rad/s²
