AP Physics 1 SI Units, Equations, and Definitions

Vocabulary and definition flashcards summarizing SI units, base units, and fundamental equations for AP Physics 1.

Displacement ($x$)

SI Unit: meter ($\text{m}$); Base Units: $\text{m}$

Mass ($m$)

SI Unit: kilogram ($\text{kg}$); Base Units: $\text{kg}$

Time / Period ($t, T$)

SI Unit: second ($\text{s}$); Base Units: $\text{s}$

Velocity ($v$)

SI Unit: $\text{m/s}$; Base Units: \text{m\,s^{-1}}

Acceleration ($a$)

SI Unit: \text{m/s^2}; Base Units: \text{m\,s^{-2}}

Force ($F$)

SI Unit: Newton ($\text{N}$); Base Units: \text{kg\,m\,s^{-2}}

Momentum ($p$)

SI Unit: $\text{kg\,m/s}$; Base Units: \text{kg\,m\,s^{-1}}

Impulse ($J$)

SI Unit: $\text{N\,s}$; Base Units: \text{kg\,m\,s^{-1}}

Energy / Work ($E, W$)

SI Unit: Joule ($\text{J}$); Base Units: \text{kg\,m^2\,s^{-2}}

Power ($P$)

SI Unit: Watt ($\text{W}$); Base Units: \text{kg\,m^2\,s^{-3}}

Pressure ($P$)

SI Unit: Pascal ($\text{Pa}$); Base Units: \text{kg\,m^{-1}\,s^{-2}}

Density ($\rho$)

SI Unit: \text{kg/m^3}; Base Units: \text{kg\,m^{-3}}

Torque ($\tau$)

SI Unit: $\text{N\,m}$; Base Units: \text{kg\,m^2\,s^{-2}}

Newton’s Second Law

Net force causes acceleration proportional to mass ($F = ma$).

Friction

Force opposing motion between surfaces ($f = \mu N$).

Universal Gravitation

Force between two masses ($F = \frac{Gm_1m_2}{r^2}$).

Centripetal Force

Net inward force for circular motion ($F_c = \frac{mv^2}{r}$).

Centripetal Acceleration

Acceleration toward center of circular path ($a_c = \frac{v^2}{r}$).

Work

Energy transferred by force over displacement ($W = Fd\cos(\theta)$).

Power (Definition)

Rate of doing work or transferring energy ($P = \frac{W}{t}$).

Kinetic Energy

Energy of motion ($K = \frac{1}{2}mv^2$).

Rotational Kinetic Energy

Energy of rotational motion ($K = \frac{1}{2}I\omega^2$).

Gravitational Potential Energy

Stored energy due to height ($U_g = mgh$).

Elastic Potential Energy

Stored energy in a spring ($U_s = \frac{1}{2}kx^2$).

Mechanical Energy

Sum of kinetic and potential energies ($E = K + U$).

Work-Energy Theorem

Net work equals change in kinetic energy ($W_{net} = \Delta K$).

Momentum

Quantity of motion ($p = mv$).

Impulse-Momentum Theorem

Impulse changes momentum ($F\Delta t = \Delta p$).

Conservation of Momentum

Total momentum remains constant in isolated systems ($p_i = p_f$).

Linear/Rotational Bridge Equations

Equations that connect translational and rotational motion ($v = r\omega$, $a = r\alpha$, $s = r\theta$).

Moment of Inertia

Resistance to rotational acceleration ($I = mr^2$ for a point mass).

Torque (Definition)

Turning effect of force ($\tau = rF\sin(\theta)$).

Rotational Newton’s 2nd Law

Net torque causes angular acceleration ($\tau = I\alpha$).

Angular Momentum

Rotational momentum ($L = I\omega$).

Conservation of Angular Momentum

Angular momentum stays constant if no external torque acts ($L_i = L_f$).

Hooke’s Law

Spring restoring force proportional to displacement ($F = -kx$).

Spring Period

Time for one oscillation of mass-spring system ($T = 2\pi \sqrt{\frac{m}{k}}$).

Pendulum Period

Time for one oscillation of simple pendulum ($T = 2\pi \sqrt{\frac{L}{g}}$).

Wave Speed

Speed of a wave ($v = f\lambda$).

General Wave Function

Describes sinusoidal wave displacement ($y = A\sin(kx - \omega t)$).

SHM Max Velocity

Maximum speed in simple harmonic motion ($v_{max} = A\omega$).

SHM Max Acceleration

Maximum acceleration in SHM ($a_{max} = A\omega^2$).

Pressure (Definition)

Force per area ($P = \frac{F}{A}$).

Pascal’s Principle

Pressure applied to fluid transmits equally throughout fluid ($\frac{F_1}{A_1} = \frac{F_2}{A_2}$).

Bernoulli’s Equation

Relates pressure, speed, and height in fluid flow ($P + \frac{1}{2}\rho v^2 + \rho gh = \text{constant}$).

Continuity Equation

Flow rate remains constant for incompressible fluid ($A_1 v_1 = A_2 v_2$).

Buoyant Force

Upward force equals weight of displaced fluid ($F_b = \rho V g$).

Volume Flow Rate

Fluid volume passing per second ($Q = Av$).