Question 1

What is moment of inertia?

Accepted Answer

Moment of inertia (I) is the rotational equivalent of mass. It measures an object's resistance to changes in angular velocity and depends on mass distribution relative to the rotation axis.

Question 2

What are the rotational kinematics equations?

Accepted Answer

The four rotational SUVAT equations are: ω_f = ω_i + αt, θ = ω_i·t + ½αt², ω_f² = ω_i² + 2αθ, and θ = ½(ω_i + ω_f)t. Given 3 of the 5 variables, the other 2 can be solved.

Question 3

What is angular momentum?

Accepted Answer

Angular momentum L = Iω is conserved in the absence of external torques. This is why a spinning skater speeds up when pulling in their arms — reducing I increases ω to keep L constant.

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