http://www.ck12.org
sin(θ) =b/c→b=c·sin(θ)
cos(θ) =a/c→a=c·cos(θ)
tan(θ) =b/a→b=a·tan(θ)
c^2 =a^2 +b^2
180 ◦=πradians
Ccircle= 2 πR
Acircle=πR^2
Vs phere= ( 4 / 3 )πR^3
Vcylinder=πR^2 h
IfXis any unit, then...
1 mX= 0 .001 X= 10 −^3 X
1 μX= 0 .000001 X= 10 −^6 X
1 nX= 0 .000000001 X= 10 −^9 X
1 kX=1000 X= 103 X
1 MX=1000000 X= 106 X
1 GX=1000000000 X= 109 X
Ifax^2 +bx+c=0, then...
x=
−b±
√
b^2 − 4 ac
2 a
% difference = |(measured – accepted) / accepted |×100%
vector dot product:a·b=abcosθ(product is a scalar)—θis angle between vectors
vector cross product:a×b=absinθ(direction is given by RHR)
Kinematics Under Constant Acceleration
4 x=xf inal−xinitial
4 (anything)=final value−initial value
vavg= 4 x/ 4 t
aavg= 4 v/ 4 t