ROTATIONAL MOTION

What is the rotational analogue of Newton’s second law for a system of particles?

• F = ma
• dP/dt = F_ext
• τ = Iα
• dL/dt = τ_ext

What is the consequence of τ_ext = 0 on the system's angular momentum?

• L increases linearly
• L decreases to zero
• L oscillates
• L remains constant

What happens to internal torques if inter-particle forces are central?

• They add constructively
• They cause rotation of the center of mass
• They cancel in pairs
• They depend on angular velocity

How is the total angular momentum of a system defined?

• L = Σ m_i v_i
• L = Iω
• L = Σ l_i, where l_i is angular momentum of ith particle
• L = r × P_total

What does the equation dL/dt = τ_ext represent?

• Law of inertia for rotation
• Conservation of energy
• Rotational analogue of Newton’s second law for systems
• Kinematic equation for rotation