Key Equations

Key Equations

DisplacementΔx=xf−xiΔx=xf−xi
Total displacementΔxTotal=∑ ΔxiΔxTotal=∑ Δxi
Average velocityv–=ΔxΔt=x2−x1t2−t1v–=ΔxΔt=x2−x1t2−t1
Instantaneous velocityv(t)=dx(t)dtv(t)=dx(t)dt
Average speedAverage speed=s–=Total distanceElapsed timeAverage speed=s–=Total distanceElapsed time
Instantaneous speedInstantaneous speed=|v(t)|Instantaneous speed=|v(t)|
Average accelerationa–=ΔvΔt=vf−v0tf−t0a–=ΔvΔt=vf−v0tf−t0
Instantaneous accelerationa(t)=dv(t)dta(t)=dv(t)dt
Position from average velocityx=x0+v–tx=x0+v–t
Average velocity (for constant acceleration)v–=v0+v2v–=v0+v2
Velocity from accelerationv=v0+at(constanta)v=v0+at(constanta)
Position from velocity and accelerationx=x0+v0t+12at2(constanta)x=x0+v0t+12at2(constanta)
Velocity from distancev2=v02+2a(x−x0)(constanta)v2=v02+2a(x−x0)(constanta)
Velocity of free fallv=v0−gt(positive upward)v=v0−gt(positive upward)
Height of free fally=y0+v0t−12gt2y=y0+v0t−12gt2
Velocity of free fall from heightv2=v02−2g(y−y0)v2=v02−2g(y−y0)
Velocity from accelerationv(t)=∫a(t)dt+C1v(t)=∫a(t)dt+C1
Position from velocityx(t)=∫v(t)dt+C2x(t)=∫v(t)dt+C2