AP Physics 2: Algebra-Based

The Physics 2 equation sheet, annotated for 2026

Transcribed from the equations table of the official AP Physics 2: Algebra-Based Course and Exam Description (Effective Fall 2024). College Board provides this sheet on both sections of the exam, so nothing here needs memorizing; knowing when each equation applies is the skill the exam actually tests. The geometry and math reference tables printed alongside the equations are not reproduced here.

For the units these equations belong to, see the Physics 2 course hub.

Constants and Conversion Factors

N0=6.02×1023 mol1N_0 = 6.02 \times 10^{23}\ \text{mol}^{-1}

Avogadro's number

R=8.31 J/(molK)R = 8.31\ \text{J/(mol} \cdot \text{K)}

Universal gas constant

kB=1.38×1023 J/Kk_B = 1.38 \times 10^{-23}\ \text{J/K}

Boltzmann's constant

1 atm=1.0×105 N/m2=1.0×105 Pa1\ \text{atm} = 1.0 \times 10^5\ \text{N/m}^2 = 1.0 \times 10^5\ \text{Pa}

1 atmosphere of pressure

k=14πε0=9.0×109 Nm2/C2k = \frac{1}{4\pi\varepsilon_0} = 9.0 \times 10^9\ \text{N} \cdot \text{m}^2/\text{C}^2

Coulomb constant

mp=1.67×1027 kgm_p = 1.67 \times 10^{-27}\ \text{kg}

Proton mass

mn=1.67×1027 kgm_n = 1.67 \times 10^{-27}\ \text{kg}

Neutron mass

me=9.11×1031 kgm_e = 9.11 \times 10^{-31}\ \text{kg}

Electron mass

e=1.60×1019 Ce = 1.60 \times 10^{-19}\ \text{C}

Elementary charge

ε0=8.85×1012 C2/(Nm2)\varepsilon_0 = 8.85 \times 10^{-12}\ \text{C}^2/(\text{N} \cdot \text{m}^2)

Vacuum permittivity

μ0=4π×107 (Tm)/A\mu_0 = 4\pi \times 10^{-7}\ (\text{T} \cdot \text{m})/\text{A}

Vacuum permeability

1 eV=1.60×1019 J1\ \text{eV} = 1.60 \times 10^{-19}\ \text{J}

1 electron volt

h=6.63×1034 Js=4.14×1015 eVsh = 6.63 \times 10^{-34}\ \text{J} \cdot \text{s} = 4.14 \times 10^{-15}\ \text{eV} \cdot \text{s}

Planck's constant

hc=1.99×1025 Jm=1240 eVnmhc = 1.99 \times 10^{-25}\ \text{J} \cdot \text{m} = 1240\ \text{eV} \cdot \text{nm}
c=3.00×108 m/sc = 3.00 \times 10^8\ \text{m/s}

Speed of light

b=2.90×103 mKb = 2.90 \times 10^{-3}\ \text{m} \cdot \text{K}

Wien's constant

σ=5.67×108 W/(m2K4)\sigma = 5.67 \times 10^{-8}\ \text{W}/(\text{m}^2 \cdot \text{K}^4)

Stefan-Boltzmann constant

1 u=1.66×1027 kg=931 MeV/c21\ \text{u} = 1.66 \times 10^{-27}\ \text{kg} = 931\ \text{MeV}/c^2

1 unified atomic mass unit

G=6.67×1011 m3/(kgs2)=6.67×1011 Nm2/kg2G = 6.67 \times 10^{-11}\ \text{m}^3/(\text{kg} \cdot \text{s}^2) = 6.67 \times 10^{-11}\ \text{N} \cdot \text{m}^2/\text{kg}^2

Universal gravitational constant

g=9.8 m/s2g = 9.8\ \text{m/s}^2

Magnitude of the acceleration due to gravity at Earth's surface

g=9.8 N/kgg = 9.8\ \text{N/kg}

Magnitude of the gravitational field strength at Earth's surface

Electricity

FE=14πε0q1q2r2=kq1q2r2\left| \vec{F}_E \right| = \frac{1}{4\pi\varepsilon_0} \frac{|q_1 q_2|}{r^2} = k \frac{|q_1 q_2|}{r^2}
E=FEq\vec{E} = \frac{\vec{F}_E}{q}
E=14πε0qr2=kqr2\left| \vec{E} \right| = \frac{1}{4\pi\varepsilon_0} \frac{|q|}{r^2} = k \frac{|q|}{r^2}
UE=14πε0q1q2r=kq1q2rU_E = \frac{1}{4\pi\varepsilon_0} \frac{q_1 q_2}{r} = k \frac{q_1 q_2}{r}
ΔUE=qΔV\Delta U_E = q \Delta V
V=14πε0iqiriV = \frac{1}{4\pi\varepsilon_0} \sum_i \frac{q_i}{r_i}
E=ΔVΔr\left| \vec{E} \right| = \left| \frac{\Delta V}{\Delta r} \right|
C=QΔVC = \frac{Q}{\Delta V}
C=κε0AdC = \frac{\kappa \varepsilon_0 A}{d}
EC=Qκε0AE_C = \frac{Q}{\kappa \varepsilon_0 A}
UC=12QΔVU_C = \frac{1}{2} Q \Delta V
I=ΔqΔtI = \frac{\Delta q}{\Delta t}
R=ρAR = \frac{\rho \ell}{A}
P=IΔVP = I \Delta V
I=ΔVRI = \frac{\Delta V}{R}
Req,s=iRiR_{\text{eq,s}} = \sum_i R_i
1Req,p=i1Ri\frac{1}{R_{\text{eq,p}}} = \sum_i \frac{1}{R_i}
1Ceq,s=i1Ci\frac{1}{C_{\text{eq,s}}} = \sum_i \frac{1}{C_i}
Ceq,p=iCiC_{\text{eq,p}} = \sum_i C_i
τ=ReqCeq\tau = R_{\text{eq}} C_{\text{eq}}

Magnetism

FB=qvBsinθF_B = q v B \sin\theta
B=μ0I2πrB = \frac{\mu_0 I}{2\pi r}
FB=IBsinθF_B = I \ell B \sin\theta
ΦB=BA\Phi_B = \vec{B} \cdot \vec{A}
ΦB=BcosθA\Phi_B = \left| \vec{B} \right| \cos\theta \left| \vec{A} \right|
E=ΔΦBΔt\left| \mathcal{E} \right| = \left| \frac{\Delta \Phi_B}{\Delta t} \right|

emf, printed as script E on the official sheet

E=Bv\mathcal{E} = B \ell v

emf

Thermal Physics

P=FAP = \frac{F_{\perp}}{A}
Kavg=32kBT=12mvrms2K_{\text{avg}} = \frac{3}{2} k_B T = \frac{1}{2} m v_{\text{rms}}^2
QΔt=kAΔTL\frac{Q}{\Delta t} = \frac{k A \Delta T}{L}
PV=nRT=NkBTP V = n R T = N k_B T
U=32nRT=32NkBTU = \frac{3}{2} n R T = \frac{3}{2} N k_B T
W=PΔVW = -P \Delta V
ΔU=Q+W\Delta U = Q + W
Q=mcΔTQ = m c \Delta T

Waves, Sound, and Optics

λ=vf\lambda = \frac{v}{f}
n=cvn = \frac{c}{v}
n1sinθ1=n2sinθ2n_1 \sin\theta_1 = n_2 \sin\theta_2
1si+1so=1f\frac{1}{s_i} + \frac{1}{s_o} = \frac{1}{f}
M=hiho=siso|M| = \left| \frac{h_i}{h_o} \right| = \left| \frac{s_i}{s_o} \right|
ΔD=mλ\Delta D = m \lambda
ΔD=asinθ\Delta D = a \sin\theta
ayminLmλa \frac{y_{\text{min}}}{L} \approx m \lambda
ΔD=dsinθ\Delta D = d \sin\theta
dymaxLmλd \frac{y_{\text{max}}}{L} \approx m \lambda
vstring=FTm/v_{\text{string}} = \sqrt{\frac{F_T}{m/\ell}}
T=1fT = \frac{1}{f}
x(t)=Acos(ωt)=Acos(2πft)x(t) = A \cos(\omega t) = A \cos(2\pi f t)
y(x)=Acos(2πxλ)y(x) = A \cos\left( \frac{2\pi x}{\lambda} \right)
fbeat=f1f2\left| f_{\text{beat}} \right| = |f_1 - f_2|

Modern Physics

E=hfE = h f
λ=hp\lambda = \frac{h}{p}
λ=cf\lambda = \frac{c}{f}
λmax=bT\lambda_{\text{max}} = \frac{b}{T}
P=AσT4P = A \sigma T^4
Kmax=hfϕK_{\text{max}} = h f - \phi
Δλ=hmec(1cosθ)\Delta \lambda = \frac{h}{m_e c} (1 - \cos\theta)
E=mc2E = m c^2
N=N0eλtN = N_0 e^{-\lambda t}
λ=ln2t1/2\lambda = \frac{\ln 2}{t_{1/2}}

Mechanics and Fluids

vx=vx0+axtv_x = v_{x0} + a_x t
x=x0+vx0t+12axt2x = x_0 + v_{x0} t + \frac{1}{2} a_x t^2
vx2=vx02+2ax(xx0)v_x^2 = v_{x0}^2 + 2 a_x (x - x_0)
xcm=imixiimi\vec{x}_{\text{cm}} = \frac{\sum_i m_i \vec{x}_i}{\sum_i m_i}
asys=Fmsys=Fnetmsys\vec{a}_{\text{sys}} = \frac{\sum \vec{F}}{m_{\text{sys}}} = \frac{\vec{F}_{\text{net}}}{m_{\text{sys}}}
Fg=Gm1m2r2\left| \vec{F}_g \right| = \frac{G m_1 m_2}{r^2}
FfμFN\left| \vec{F}_f \right| \leq \left| \mu \vec{F}_N \right|
Fs=kΔx\vec{F}_s = -k \Delta \vec{x}
ac=v2ra_c = \frac{v^2}{r}
K=12mv2K = \frac{1}{2} m v^2
W=Fd=FdcosθW = F_{\parallel} d = F d \cos\theta
ΔK=iWi=iF,idi\Delta K = \sum_i W_i = \sum_i F_{\parallel, i}\, d_i
Us=12k(Δx)2U_s = \frac{1}{2} k (\Delta x)^2
UG=Gm1m2rU_G = -\frac{G m_1 m_2}{r}
ΔUg=mgΔy\Delta U_g = m g \Delta y
Pavg=WΔt=ΔEΔtP_{\text{avg}} = \frac{W}{\Delta t} = \frac{\Delta E}{\Delta t}
Pinst=Fv=FvcosθP_{\text{inst}} = F_{\parallel} v = F v \cos\theta
p=mv\vec{p} = m \vec{v}
Fnet=ΔpΔt=mΔvΔt=ma\vec{F}_{\text{net}} = \frac{\Delta \vec{p}}{\Delta t} = m \frac{\Delta \vec{v}}{\Delta t} = m \vec{a}
J=FavgΔt=Δp\vec{J} = \vec{F}_{\text{avg}} \Delta t = \Delta \vec{p}
vcm=ipiimi=imiviimi\vec{v}_{\text{cm}} = \frac{\sum_i \vec{p}_i}{\sum_i m_i} = \frac{\sum_i m_i \vec{v}_i}{\sum_i m_i}
ω=ω0+αt\omega = \omega_0 + \alpha t
θ=θ0+ω0t+12αt2\theta = \theta_0 + \omega_0 t + \frac{1}{2} \alpha t^2
ω2=ω02+2α(θθ0)\omega^2 = \omega_0^2 + 2 \alpha (\theta - \theta_0)
v=rωv = r \omega
aT=rαa_T = r \alpha
τ=rF=rFsinθ\tau = r_{\perp} F = r F \sin\theta
I=imiri2I = \sum_i m_i r_i^2
I=Icm+Md2I' = I_{\text{cm}} + M d^2
αsys=τIsys=τnetIsys\alpha_{\text{sys}} = \frac{\sum \tau}{I_{\text{sys}}} = \frac{\tau_{\text{net}}}{I_{\text{sys}}}
K=12Iω2K = \frac{1}{2} I \omega^2
W=τΔθW = \tau \Delta\theta
L=IωL = I \omega
L=rmvsinθL = r m v \sin\theta
ΔL=τΔt\Delta L = \tau \Delta t
Δxcm=rΔθ\Delta x_{\text{cm}} = r \Delta\theta
T=1fT = \frac{1}{f}
Ts=2πmkT_s = 2\pi \sqrt{\frac{m}{k}}
Tp=2πgT_p = 2\pi \sqrt{\frac{\ell}{g}}
x=Acos(2πft)x = A \cos(2\pi f t)
x=Asin(2πft)x = A \sin(2\pi f t)
ρ=mV\rho = \frac{m}{V}
P=FAP = \frac{F_{\perp}}{A}
P=P0+ρghP = P_0 + \rho g h
Pgauge=ρghP_{\text{gauge}} = \rho g h
Fb=ρVgF_b = \rho V g
A1v1=A2v2A_1 v_1 = A_2 v_2
P1+ρgy1+12ρv12=P2+ρgy2+12ρv22P_1 + \rho g y_1 + \frac{1}{2} \rho v_1^2 = P_2 + \rho g y_2 + \frac{1}{2} \rho v_2^2

The other sheets