equations Flashcards
word, symbol and units of speed equation
speed = distance / time
s = d/t
s = ms^-1
d = meter
t = seconds
word, symbol and units of acceleration equation
acceleration = final velocity - initial velocity / time
a = v -u/t
a = ms^-2
v = ms^-1
u = ms^-1
t = seconds
word, symbol and units of force equation
force = mass x acceleration
F = ma
F = N
m = kg
a = ms^-2
word, symbol and units of force (spring) equation
force = spring constant x extension
F = kx
F = N
k = Nm^-1
x = m
word, symbol and units of weight equation
weight = mass x gravitational field strength
w = mg
F = N
m = kg
g = 9.8KgN^-1
word, symbol and units of GPE equation
Gravitational potential energy = mass x gravitational field strength x change in height
GPE = mgh
GPE = J
m = Kg
g = 9.8Nm^-1
h = meters
word, symbol and units of KE equation
kinetic energy = 1/2 x mass x velocity^2
KE = 1/2mv^2
KE = J
m = Kg
v = ms^-1
word, symbol and units of work done equation
work done = force x distance
w = Fd
w = J
F = N
d = meter
word, symbol and units of power equation
power = useful energy / time
power = useful work done/ time
P = E/w / t
P = E (energy)/ w(work done)
t = seconds
word equation of efficiency
efficiency = useful energy/power / total energy/power x 100%
word, symbol and units of pressure in solid equation
pressure = force / area
P = F/A
P = Pa / Nm ^2 / Ncm ^2
F = N
A = m^2 / cm ^2
word, symbol and units of moment equation
moment = force x perpendicular distance from pivot
m = Fd
m = Nm
F = N
d = meters
word, symbol and units of pressure in liquids equation
Pressure = height x density x gravity
P = hpg
P = Pa / Nm ^2 / Ncm ^2
h = m
p = Kg/ dm ^3
g = Nkg ^-1
word, symbol and units of density equation
p = m / V
density = mass / volume
p = kgm ^-3 / gcm ^-3
m =kg
V =m ^3
word, symbol and units of wave speed
V = fλ
velocity = frequency x wave length
V= velocity (ms^-1)
f=frequency (Hz)
λ= wave length (m)
word, symbol and units of period
T = 1/ f
time = 1/ frequency
T= time (s)
f= frequency (Hz)
Snell’s law
n = sin ( i angle ) / sin( r angle )
3 formulas to find refractive index
- n = sin ( i angle ) / sin ( r angle )
- n = 1/ sin ( C - critical angle )
- n = c - speed of light in vacuum / speed of light in medium
( use sin^-1 if needed to convert to angle)
word, symbol & units for magnification formula
-image distance from optic center/ obj distance from optic center
-no units & symbols
word, symbol & units for power of lens formula
- 1/ focal length
- P = 1/ f
P = m^-1
f = m
-positive for convex lens
-negative for concave lens
