Physics formulas to memorize

basic kinematics

change in x=v0t+(.5)at²

v²=v0²+2a(change in x)

planetary body gravity

F=(Gm1m2)/r²

gravitational field

 g=GM/r²

energy

K=.5mv²
U=mgh

U(elastic)=.5kx²

power

W/t

Impulse

J=change in p = Ft

inelastic vs elastic collisions

inelastic —> energy not conserved, objects stick

angular converstions

x=r(feta)

v=rw

a=ra

centripetal force

v²/r=w²r

bank with no friction

v=root(grtan)

torque

T=rFsin(feta)=Ia

rotational intertia

I=mr² (hoop/ring)

I=.5mr² (cylinder)

I=.4mr² (sphere)

(mass further from the center —> greater I)

K rot

Iw²

Angular momentum

L=Iw

Angular impulse

T*change in time

parallel axis theorem

I(new)=I(central)+md²

spring restoring force

F=-kx

period (T) for springs

T=2π*(m/k)^.5

x function harmonic motion

x(t)=Acos(2πt/T)

pendulum restoring force

F=-mg(feta) (only applies if angle less than 15)

arc length

s=L(feta)

period T for pendulums

T=2π*(L/g)^.5