Classical Mechanics — 70 Terms Defined

Escape Velocity Classical Mechanics m/s The minimum speed required for a ballistic object to escape a massive body's gravitational field without further propulsion. v_esc = √(2 G M / R)

Force Classical Mechanics N (kg·m/s²) A vector interaction that, when unopposed, alters the state of motion or deforms a physical body. F = m a = dp/dt

Frequency (Mechanics) Classical Mechanics Hz (s⁻¹) The number of complete vibrational cycles occurring per unit time. f = 1 / T = ω / (2π)

Friction Classical Mechanics N A resistive contact force that opposes relative sliding motion or tendency of motion between surfaces. fs ≤ μs N, fk = μk N

Gravity Classical Mechanics N The universal attractive force between masses, causing mutual acceleration proportional to mass and inversely proportional to squared distance. Fg = G m1 m2 / r²

Hooke's Law Classical Mechanics N (k in N/m) A law of elasticity stating that restoring force exerted by a spring or elastic material is proportional to its extension or compression distance. F = -k x

Impulse Classical Mechanics N·s (or kg·m/s) The vector quantity defined as the integral of a force over the time interval during which it acts, equal to the net change in momentum. J = ∫ F dt = Δp = m vf - m vi

Inclined Plane Classical Mechanics Dimensionless A simple machine consisting of a flat supporting surface tilted at an angle to the horizontal. MA = L / h = 1 / sin θ

Inelastic Collision Classical Mechanics kg·m/s, J A collision in which total linear momentum is conserved, but total kinetic energy is not conserved. ∑ p_i = ∑ p_f, KE_final < KE_initial

Inertia Classical Mechanics kg The natural resistance of any physical object to any change in its velocity or state of motion. Quantified by Mass (m)

Kinetic Energy Classical Mechanics J The scalar energy an object possesses by virtue of its motion, proportional to its mass and the square of its speed. KE = ½ m v²

Maximum Height Classical Mechanics m The maximum vertical elevation reached by a projectile above its launch level, where vertical velocity momentarily becomes zero. H = (v0² sin² θ) / (2 g)

Mechanical Advantage Classical Mechanics Dimensionless The factor by which a simple machine multiplies input effort force to overcome load resistance. MA = F_output / F_input

Mechanical Energy Classical Mechanics J The sum of kinetic energy and potential energy in a physical system. E_mech = KE + PE

Moment of Inertia Classical Mechanics kg·m² A quantitative measure of a body's rotational inertia - its resistance to changes in rotational motion about a given axis. I = ∑ m_i r_i² = ∫ r² dm

Momentum Classical Mechanics kg·m/s A fundamental vector quantity equal to the product of an object's mass and its velocity, representing its quantity of motion. p = m v

Newton's First Law Classical Mechanics N/A The principle that an object remains at rest or continues in uniform motion in a straight line unless acted upon by a net external force. ∑ F = 0 ⇒ v = constant

Newton's Second Law Classical Mechanics N The law stating that net force acting on a body equals the rate of change of its linear momentum, simplified to mass times acceleration for constant mass. F_net = m a

Newton's Third Law Classical Mechanics N The law stating that whenever two objects interact, they exert forces on each other that are equal in magnitude and opposite in direction. F_A_to_B = -F_B_to_A

Non-conservative Force Classical Mechanics N A force for which work done depends on the specific path taken, dissipating mechanical energy into heat, sound, or internal energy. W_non-cons = ΔME = ΔKE + ΔPE

Normal Force Classical Mechanics N The perpendicular contact force exerted by a surface on an object pressing against it. N = m g cos θ

Orbital Velocity Classical Mechanics m/s The speed required for a body to maintain a stable circular orbit around a primary gravitational mass at a given radius. v_orb = √(G M / r)

Parallel Axis Theorem Classical Mechanics kg·m² A theorem stating that the moment of inertia about any axis parallel to a centroidal axis equals the centroidal moment of inertia plus mass times squared offset distance. I = I_cm + M d²

Pascal's Principle Classical Mechanics Pa The principle stating that pressure applied to an enclosed fluid is transmitted undiminished to every portion of the fluid and container walls. ΔP = F1 / A1 = F2 / A2