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Key Equations

Position vector r (t)=x(t)i^ +y(t)j^ +z(t)k^
Displacement vector Δr =r (t2)r (t1)
Velocity vector v (t)=lim Δt0 r (t+Δt)r (t) Δt =dr dt
Velocity in terms of components v (t)=vx(t)i^ +vy(t)j^ +vz(t)k^
Velocity components vx(t)=dx(t) dt vy(t)=dy(t) dt vz(t)=dz(t) dt
Average velocity v avg=r (t2)r (t1) t2t1
Instantaneous acceleration a (t)=lim t0 v (t+Δt)v (t) Δt =dv (t) dt
Instantaneous acceleration, component form a (t)=dvx(t) dt i^ +dvy(t) dt j^ +dvz(t) dt k^
Instantaneous acceleration as second
derivatives of position
a (t)=d2x(t) dt2 i^ +d2y(t) dt2 j^ +d2z(t) dt2 k^
Time of flight Ttof=2(v0sinθ0) g
Trajectory y=(tanθ0)x[g2(v0cosθ0)2 ] x2
Range R=v02sin2θ0 g
Centripetal acceleration aC=v2 r
Position vector, uniform circular motion r (t)=Acosωti^ +Asinωtj^
Velocity vector, uniform circular motion v (t)=dr (t) dt =Aωsinωti^ +Aωcosωtj^
Acceleration vector, uniform circular motion a (t)=dv (t) dt =Aω2cosωti^ Aω2sinωtj^
Tangential acceleration aT=d|v | dt
Total acceleration a =a C+a T
Position vector in frame
S is the position
vector in frame S plus the vector from the
origin of S to the origin of S
r PS=r PS+r SS
Relative velocity equation connecting two
reference frames
v PS=v PS+v SS
Relative velocity equation connecting more
than two reference frames
v PC=v PA+v AB+v BC
Relative acceleration equation a PS=a PS+a SS
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