equations

Weight (w)

Weight (w)

Mass x gravitational field strength (m g)

Work done (W)

force (F) x distance (along the line of action of the force)

Force applied to a spring (F)

Spring constant x extension (k e)

moment of a force (M)

Force x distance (normal to the direction of the force) (F d)

Pressure (P)

force normal to a surface (F) divided by the area of that surface (a)

Distance travelled (S)

Speed (v) x time (t)

acceleration (a)

change in velocity (Δ v)/time taken (t)

resultant force (F)

mass (m) x acceleration (a)

momentum (p)

mass (m) x velocity (v)

Kinetic energy (E,K)

0.5 (1/2) x mass (m)x speed2 (v2)

gravitational potential energy (Ep)

mass (m) x gravitational field strength (g) x height (h)

power (P) (1)

energy (E)/time(t)

power (P) (2)

work done(w)/time(t)

Efficiency (2)

Useful power output / total power input

Efficiency (1)

Useful output energy transfer / total input energy transfer

wave speed (v)

frequency (f) x wavelength (λ)

charge flow (Q)

Current (I) x time (t)

Potential difference(v)

current (I)x resistance(R)

Power (P) (1)

potential difference (V) x current (I)

Power (P) (2)

current2 (I2)x resistance(R)

energy transferred (E) (1)

Power (P) x time (t)

Energy transferred (E) (2)

charge flow (Q) x potential difference (V)

Density (p)

mass (m) / volume (v)