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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 Δt→0 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) t2−t1
Instantaneous acceleration a→ (t)=lim t→0 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→ S′S
Relative velocity equation connecting two
reference frames
v→ PS=v→ PS′+v→ S′S
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→ S′S
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