charge

current x time

acceleration

(v-u)/t

speed

distance/time

force

mass x acceleration

wave speed

frequency x wavelength

density

mass/volume

pressure

force/area

pressure difference

density x gravity x height

power

current x voltage

weight

mass x gravity

moment

force x perpendicular distance

force (springs)

spring constant x change in extension

thermal energy

mass x shc x change in temperature

GPE

mass x gravity x height

work done

force x distance

power (in terms of work done)

work done/time

kinetic energy

1/2 x mass x (velocity)2

momentum

mass x velocity

force (in terms of momentum)

change in momentum/time taken for change

(final velocity)2

(initial velocity)2 + (2 x acceleration x displacement)

critical angle

sinC = 1/n (=refractive index)

input and output voltage

V2/V1 = N2/N1

pressure/temperature

P1/T1 = P2/T2

degrees Celsius to kelvin

add 273

refractive index

sin i (incident ray) / sin r (refractive ray)

efficiency

(useful energy output / total energy output) x 100

pressure law (pressure and volume)

P1 x V1 = P2 x V2

red shift

change in wavelength / reference wavelength = velocity of a galaxy / speed of light (3x10^8)