Final answer:
The given equation ω = (20 - 1/2)t indicates that the system is experiencing angular deceleration since angular velocity decreases with time, not uniform circular motion or simple harmonic motion.
Step-by-step explanation:
The question pertains to the concept of angular velocity and angular acceleration in Physics, specifically in the context of rotational motion. From the given angular velocity equation ω = (20 - 1/2)t, we can observe that the angular velocity is not constant because it varies with time depeding on the value of t. The term –(1/2)t suggests that the angular velocity decreases linearly as time increases, which is indicative of angular deceleration. This is not uniform circular motion, which requires a constant angular velocity, nor is it simple harmonic motion, which involves sinusoidal variation of angular position. Hence, the correct answer to the question is D) Angular deceleration.
Remember, angular acceleration (α) is defined as the rate of change of angular velocity. For a linear relationship between angular velocity and time, such as the one given, the angular acceleration is constant. This constant value can be found by taking the derivative of the angular velocity equation with respect to time.