Work and Energy

Collisions

Inelastic: Kinetic energy and momentum is conserved
Elastic: Momentum is conserved

Equations

If Straight

$$W=Fdcos(\theta )$$

OR

$$W={\int }_A^B\vec{F}\cdot d\vec{l}$$

$\theta$ is angle between distance and force

$$K=0.5m{v}^2$$ $$\sqrt{\frac{2K}{m}}=v$$

K is kenetic energy in Jules

$$\Delta U=mgh$$

• On any path, a force constant in magnitude and direction will do the same amount of work

$$W_{nc}=U_i+K_i-U_f-K_f$$

momentum (newton seconds) =
$P$ = momentum in $kgm/s$
$m$ = mass in kg
$v$ = velocity in m/s

$$P=mv$$ $$\Delta P=m\Delta v$$ $$\Delta P=J$$

Impulse (newton seconds) =
$J$ = impulse in $kgm/s$
$F$ = force in N

$$J=Ft$$ $$J=m\Delta v$$