speed
distance/time
average velocity
total distance/total time
acceleration
change in velocity/change in time
weight
mass x gravitational field strength
density
mass/volume
hookes law
force= spring constant x extension
newtons second law
force= mass x acceleration
moment
force x perpendicular distance from pivot
principle of moments
sum of clockwise moments = sum of anticlockwise moments
momentum
mass x velocity
impulse
impulse = change in momentum
impulse
force x time
work
force x distance moved
power
work/time
kinetic energy
½ x mass x velocity2
gravitational potential energy
mass x gravitational pull x height
efficiency (power)
useful power output/total power input x 100
efficiency (energy)
useful energy output/total energy input x 100
pressure (on a surface)
force/area
fluid pressure
density x gravitational pull x height
Boyles law (constant temperature)
pressure x volume = constant
specific heat capacity
change in energy/mass x temperature change
temperature in kelvin
temperature + 273
wave speed
frequency x wavelength
frequency
1/ time period
refractive index (refraction)
sine of angle of incidence/sine of refraction
refractive index (light speed)
speed of light in vacuum/speed of light in medium
refractive index (critical angle)
1/sine of critical angle
current
charge/time
e.m.f
work done on charge/charge
potential difference
work done by charge/ charge
ohms law
current x resistance
power
current x voltage
power loss
current2 x resistance
energy transferred (current)
p.d x current x time
energy transferred (power)
power x time
potential divider
ratio of resistances = ratio of p.d
resistors in series
total resistance = sum of resistors
resistors in parallel
total resistance= inverse sum of resistances
transformer equation
secondary voltage/primary voltage = turns in secondary coil/ turns in primary coil
transformers (100% power transfer)
primary voltage/secondary voltage = secondary current/primary current
radioactive alpha decay
radioactive beta decay
radioactive gamma decay
average orbital speed
orbital circumference/time period
Hubble constant
recessional velocity/ distance to galaxy
estimate for age of the universe
1/hubble constant