qwen3.5 wrote physics notes

notes/phys1/phys1_unit5.txt

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+== UNIT 5: TORQUE AND ROTATIONAL DYNAMICS ==
+Torque: τ = r*F*sin(θ) = F_perp*r
+r is distance from pivot to force application point
+Lever arm: perpendicular distance from pivot to force line
+τ = I*α (rotational analog of F = ma)
+Moment of inertia: I = Σ(m_i*r_i^2)
+Parallel axis theorem: I = I_cm + M*d^2
+Rotational KE: KE_rot = 0.5*I*ω^2
+Angular momentum: L = I*ω
+Angular momentum conserved if no external torque
+Rotational work: W = τ*Δθ
+Rotational power: P = τ*ω
+Rolling without slipping: v = r*ω, a = r*α
+Static friction enables rolling
+Angular acceleration same for all points
+Angular velocity same for all points
+Angular momentum: L = m*v*r*sin(θ) for point mass
+Rotational inertia depends on mass distribution