16 lines
876 B
Plaintext
16 lines
876 B
Plaintext
== UNIT 2: FORCE AND TRANSLATIONAL DYNAMICS ==
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System: choose boundaries, internal forces cancel
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External forces cause system acceleration
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ΣF = ma (net force = mass x acceleration)
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Free-body diagram: ONLY external forces on chosen object
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Weight = mg (field force)
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Normal force: contact perpendicular, NOT always equal to weight
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Friction: kinetic = μ_k*F_N, static ≤ μ_s*F_N
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Friction opposes motion, direction opposite velocity
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Incline: resolve gravity into parallel (mg sin θ) and perpendicular (mg cos θ)
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Tension: pulls along string/rope, same throughout ideal rope
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Pulley: massless frictionless pulley transmits force unchanged
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Newton's 3rd Law: action-reaction pairs equal opposite different objects
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Mass vs weight: mass constant, weight depends on location
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Equilibrium: ΣF = 0, not necessarily zero velocity
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Terminal velocity: when drag = weight, a = 0, v constant |