Science—Physics 1 Equations

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1-D Motion

LaTeX: \left.
    \begin{array}{ll}
        \Delta x=\frac{1}{2}(v_i+v_f)t \\
        v_f=v_i+at \\
        \Delta x=v_it+\frac{1}{2}at^{2}  \\
       v_f^{2}=v_i^{2}+2a\Delta x
    \end{array}
\right \}x-dir\\
\left.
    \begin{array}{ll}
        \Delta y=\frac{1}{2}(v_i+v_f)t \\
        v_f=v_i+at \\
        \Delta y=v_it+\frac{1}{2}at^{2}  \\
       v_f^{2}=v_i^{2}+2a\Delta y
    \end{array}
\right \}y-dir\\
a=-9.8\frac{m}{s^{2}} \ (free\ fall)Δx=12(vi+vf)tvf=vi+atΔx=vit+12at2v2f=v2i+2aΔx}xdirΔy=12(vi+vf)tvf=vi+atΔy=vit+12at2v2f=v2i+2aΔy}ydira=9.8ms2 (free fall)


Vectors

LaTeX: R_{adj}=Rcos\theta\\
R_{opp}=Rsin\theta\\
R=\sqrt{R_{adj}^{2}+R_{opp}^{2} } \\
\theta=tan^{-1}\frac{R_{opp}}{R_{adj}}Radj=RcosθRopp=RsinθR=R2adj+R2oppθ=tan1RoppRadj


Projectile Motion

LaTeX: \left.
    \begin{array}{ll}
        v_{xi}=v_icos\theta  \\
        v_{xi}=v_x \\
        \Delta x=v_ysin\theta \\
    \end{array}
\right \}x-dir\\
\left.
    \begin{array}{ll}
        v_{yi}=v_ysin\theta \\
        \Delta y=v_{iy}t+\frac{1}{2}at^{2}  \\
        v_{fy}=v_{iy}+at\\
       v_{fy}^{2}=v_{iy}^{2}+2a\Delta y
    \end{array}
\right \}y-dir\\
\theta=tan^{-1}\frac{v_{fy}}{v_{fx}}\ (impact\ angle) \\
\left.
    \begin{array}{ll}
        R=\frac{v_i^{2}sin(2\theta)}{g}  \\
        H=\frac{(v_isin\theta)^{2}}{2g}  \\
        t=\frac{2v_isin\theta}{g}\\
    \end{array}
\right \}Special\ Case:\ h_i=h_f\\vxi=vicosθvxi=vxΔx=vysinθ}xdirvyi=vysinθΔy=viyt+12at2vfy=viy+atv2fy=v2iy+2aΔy}ydirθ=tan1vfyvfx (impact angle)R=v2isin(2θ)gH=(visinθ)22gt=2visinθg}Special Case: hi=hf


Forces and Torque

LaTeX: \left.
    \begin{array}{ll}
        \sum\overset{\rightharpoonup}{F}=0 \\
        \sum{F_x} = 0 \\
        \sum {F_y} = 0 \\
        \sum {\tau} = 0
    \end{array}
\right \}static\\
\left.
    \begin{array}{ll}
        \sum\overset{\rightharpoonup}{F}=m\overset{\rightharpoonup}{a} \\
        \sum{F_x} = ma_x \\
        \sum {F_y} = ma_y \\
        \sum {\tau} = I\alpha
    \end{array}
\right \}dynamic\\
F_g = mg\ (force\ due\ to\ gravity)\\
\left.
    \begin{array}{ll}
        f_s\le\mu_sF_n  \\
        f_s=\mu_kF_n  \\
    \end{array}
\right \}frictional\ forces\\
\left.
    \begin{array}{ll}
        \overset{\rightharpoonup}{R}_{liquid}=-b\overset{\rightharpoonup}{v} \\
        \overset{\rightharpoonup}{R}_{air}=\frac{1}{2}D\rho Av^{2}  \\
        v_{term} =\sqrt[]{\frac{2mg}{D\rho A} }  \\
    \end{array}
\right \}restrictive\ forces\\
F=\frac{Gm_1m_2}{r^{2}} \ (Gravitational\ force\ between\ two\ objects)\\
\tau=Frsin\thetaF=0Fx=0Fy=0τ=0}staticF=maFx=maxFy=mayτ=Iα}dynamicFg=mg (force due to gravity)fsμsFnfs=μkFn}frictional forcesRliquid=bvRair=12DρAv2vterm=2mgDρA}restrictive forcesF=Gm1m2r2 (Gravitational force between two objects)τ=Frsinθ


Work and Energy

LaTeX: W=F\Delta x cos\theta\\
\Delta K = \frac{1}{2} m\Delta v^{2}\ (Kinetic\ Energy)\\
\Delta U_g = mg\Delta h\ (Gravitational\ P.E.)\\
\Delta U_s=\frac{1}{2} k\Delta x^{2} \ (Elastic\ P.E.)\\
\left.
    \begin{array}{ll}
        W_{net} = \Delta K  \\
        W_{nc} +W_c=\Delta K
    \end{array}
\right \}Work\ Energy\ Theory\\
W_c=-\Delta U\ (Conservative)\\
W_{nc} =-f_kd\ (Non- Conservative)W=FΔxcosθΔK=12mΔv2 (Kinetic Energy)ΔUg=mgΔh (Gravitational P.E.)ΔUs=12kΔx2 (Elastic P.E.)Wnet=ΔKWnc+Wc=ΔK}Work Energy TheoryWc=ΔU (Conservative)Wnc=fkd (NonConservative)


Impulse and Momentum

LaTeX: \overset{\rightharpoonup}{p}=m\overset{\rightharpoonup}{v}\\
\overset{\rightharpoonup}{I}=\overset{\rightharpoonup}{F}\Delta t\\
\overset{\rightharpoonup}{p_i}=\overset{\rightharpoonup}{p_f}\\
\overset{\rightharpoonup}{p}_{i} =\overset{\rightharpoonup}{p}_{f}\\
m_1v_{2i} +m_2v_{2i} =m_1v_{2f} +m_2v_{2f}\ (inelastic\ and\ elastic)\\
m_1v_{2i} +m_2v_{2i} =(m_1+m_2)v_{f} \ (perfectly\ inelastic)\\
v_{1i} -v_{2i} = -(v_{1f} -v_{2f} )\ (elastic)p=mvI=FΔtpi=pfpi=pfm1v2i+m2v2i=m1v2f+m2v2f (inelastic and elastic)m1v2i+m2v2i=(m1+m2)vf (perfectly inelastic)v1iv2i=(v1fv2f) (elastic)


Angular Momentum

LaTeX: \overset{\rightharpoonup}{L}=I\omega\\
\overset{\rightharpoonup}{L}=\overset{\rightharpoonup}{r}\times \overset{\rightharpoonup}{p}\\
\overset{\rightharpoonup}{L}_i=\overset{\rightharpoonup}{L}_fL=IωL=r×pLi=Lf


Angular Motion

LaTeX: \left.
    \begin{array}{ll}
        \omega_{av}=\frac{1}{2}(\omega_i+\omega_f)   \\
        \omega_f=\omega_i+\alpha t \\
        \Delta\theta=\omega_it+\frac{1}{2}\alpha t  \\
        \omega_f^{2}=\omega_i^{2}+2\alpha\Delta\theta
    \end{array}
\right \}Angular\ Equations\ of\ Motion\\
\overset{\rightharpoonup}{r}_{cm} =\frac{\displaystyle\sum\limits_{i=1}^nm_i\overset{\rightharpoonup}{r}_{i} }{m_1+m_2+m_3+...+m_n}\ (Center\ of\ Mass)\\
\left.
    \begin{array}{ll}
        v_t=r\omega\\
        a_t=r\alpha \\
        a_c=\frac{v^{2}}{r}   \\
        a_c=r\omega^{2} \\
        F_c=ma_c
    \end{array}
\right \}Circular\ Motion\\
\left.
    \begin{array}{ll}
        I=\displaystyle\sum\limits_{i}^nm_i{r}_i^{2}  \\
        I_p=I_{cm}+mr^{2}  \\
        I_z=I_x+I_y  \\
    \end{array}
\right \}Moment\ of\ Inertiaωav=12(ωi+ωf)ωf=ωi+αtΔθ=ωit+12αtω2f=ω2i+2αΔθ}Angular Equations of Motionrcm=ni=1mirim1+m2+m3+...+mn (Center of Mass)vt=rωat=rαac=v2rac=rω2Fc=mac}Circular MotionI=nimir2iIp=Icm+mr2Iz=Ix+Iy}Moment of Inertia


Moments of Inertia of Homogeneous Rigid Objects

LaTeX: I_{CM} =MR^2\ (Hoop\ or\ thin\ cylindrical\ shell)\\
I_{CM}=\frac{1}{2} M(R_1^2+R_2^2) \ (Hollow\ cylinder)\\
I_{CM}=\frac{1}{2} MR^2 \ (Solid\ cylinder\ or\ disk)\\
I_{CM}=\frac{1}{12} M(a^2+b^2) \ (Rectangular\ plate)\\
I_{CM}=\frac{1}{12} ML^2\ (Long,\ thin\ rod\ with\ rotation\ axis\ through\ center)\\
I_{CM}=\frac{1}{3} ML^2 \ (Long,\ thin\ rod\ with\ rotation\ axis\ through\ end)\\
I_{CM}=\frac{2}{5} MR^2 \ (Solid\ sphere)\\
I_{CM}=\frac{2}{3} MR^2 \ (Thin\ spherical\ shell)\\ICM=MR2 (Hoop or thin cylindrical shell)ICM=12M(R21+R22) (Hollow cylinder)ICM=12MR2 (Solid cylinder or disk)ICM=112M(a2+b2) (Rectangular plate)ICM=112ML2 (Long, thin rod with rotation axis through center)ICM=13ML2 (Long, thin rod with rotation axis through end)ICM=25MR2 (Solid sphere)ICM=23MR2 (Thin spherical shell)


Rolling Without Slipping

LaTeX: \Delta s=r\Delta\theta\\
v_{cm}=r\omega\\
a_{cm}=r\alpha\\
\omega=\frac{v_{cm}}{r}\\
K_r=\frac{1}{2} I\omega^{2}\ (Rolling\ Kinetic\ Energy)\\
K=\frac{1}{2}  mv^{2}+\frac{1}{2} I\omega^{2}\ (Total\ Kinetic\ Energy)Δs=rΔθvcm=rωacm=rαω=vcmrKr=12Iω2 (Rolling Kinetic Energy)K=12mv2+12Iω2 (Total Kinetic Energy)


Simple Harmonic Motion (SHM)

LaTeX: F=-kx\ (Hooke's\ Law)\\
a=-\frac{k}{m} x\ (SHM\ acceleration)\\
v=\pm \sqrt{\frac{k}{m} (A^{2}-x^{2})} \ (SHM\ velocity)\\
T=2\pi\sqrt{\frac{m}{k} } \ (Period\ of\ a\ Spring)\\
\omega=\sqrt{\frac{k}{m} } \ (Angular\ Frequency)\\
\left.
    \begin{array}{ll}
        x=Acos2\pi ft  \\
        v=-A\omega sin2\pi ft \\
        a= -A\omega^{2} cos2\pi ft \\
    \end{array}
\right \}SHM\ Equations\ of\ MotionF=kx (Hookes Law)a=kmx (SHM acceleration)v=±km(A2x2) (SHM velocity)T=2πmk (Period of a Spring)ω=km (Angular Frequency)x=Acos2πftv=Aωsin2πfta=Aω2cos2πft}SHM Equations of Motion