Sections
Key Equations

Key Equations

resultant magnitude R=Rx2+Ry2R=Rx2+Ry2
resultant direction θ=tan1(Ry/Rx)θ=tan1(Ry/Rx)
x-component of a vector A (when an angle is given relative to the horizontal) Ax=AcosθAx=Acosθ
y-component of a vector A (when an angle is given relative to the horizontal) Ay=AsinθAy=Asinθ
addition of vectors Ax + Ay = AAx + Ay = A
angle of displacement θ=tan1(y/x)θ=tan1(y/x)
velocity v=vx2+vy2v=vx2+vy2
angle of velocity θv=tan1(vy/vx)θv=tan1(vy/vx)
maximum height h=v0y22gh=v0y22g
range R=v02sin2θ0gR=v02sin2θ0g
force of static friction fsμsNfsμsN
force of kinetic friction fk=μkNfk=μkN
perpendicular component of weight on an inclined plane w=wcos(θ)=mgcos(θ)w=wcos(θ)=mgcos(θ)
parallel component of weight on an inclined plane w||=wsin(θ)=mgsin(θ)w||=wsin(θ)=mgsin(θ)
Hooke’s law F=kxF=kx
period in simple harmonic motion T=2πmkT=2πmk
frequency in simple harmonic motion f=12πkmf=12πkm
period of a simple pendulum T=2πLgT=2πLg