Question

1.    What is the angular acceleration of a ball that starts at rest and increases its angular velocity uniformly to 5 rad/s in 10 s? 

Answer 1

$$\omega=\omega_0+\alpha t,$$ $$\alpha=\dfrac{\omega-\omega_0}{t}=\dfrac{5\ \dfrac{rad}{s}-0}{10\ s}=0.5\ \dfrac{rad}{s^2}.$$