This is a draft cheat sheet. It is a work in progress and is not finished yet.
P1 - energy
K.E = 1/2 mv2 |
Kinetic energy = 1/2 x mass x (velocity)2 |
EPE = 1/2 ke2 |
Elastic potential energy = 1/2 x spring constant x (extension)2 |
GPE = mgh |
Gravitational potential energy = mass x gravity x height |
TE = mCΔT |
Thermal energy = mass x specific heat capacity x change in temp. |
C = E/mΔT |
Specific heat capacity = energy / mass x change in temp. |
Efficiency = (useful energy output/ total energy input) x100 |
WD = Fs |
Work done = Force x distance |
P2 - electricity
P = E/t |
Power = energy transferred/ time |
P = WD/t |
Power = work done/ time |
P =V2/ R |
Power = (potential difference)2/ resistance |
P = IV |
Power = current x potential difference |
P = I2R |
Power = (current)2 x resistance |
Q = It |
Charge flow = current x time |
V = IR |
Potential difference = current x resistance |
E = ItV |
Energy = current x time x potential difference |
E = QV |
Energy = charge flow x potential difference |
E = Pt |
Energy transferred = power x time |
RT = R1+R2+R3... |
Series circuit total resistance |
1/RT= 1/R2+ 1/R2+ 1/R3... |
Parallel circuit total resistance |
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P3 - particle model of matter
ρ=m/V |
Density = mass/ Volume |
E=mL |
Energy for a change of state = mass x specific latent heat of fusion OR vaporisation |
PV = constant |
For gases: pressure x volume = constant |
P=F/A |
Pressure = force / area |
P5 - forces and motion
v=s/t |
Speed = distance/ time |
v=(v+u)/2 x t |
Average speed = (final speed + initial speed)/2 x time |
a=Δv/ t |
Acceleration = change in velocity/ time |
v=u+at |
Velocity = initial velocity + (acceleration x time) |
v2=u2+2as |
(Final velocity)2 = (initial velocity)2+(2 x acceleration x distance) |
s=ut+1/2 at2 |
Distance = (initial velocity x time) + (1/2 x acceleration x time2) |
W=mg |
Weight = mass x gravitational field strength |
F=ma |
Newton's 2nd: Force = mass x acceleration |
F=ke |
Force = spring constant x extension |
EPE=1/2 Fe |
Elastic potential energy = 1/2 x Force x extension |
Momentum=mv |
Momentum = mass x velocity |
F=(Δmomentum)/ t |
Force = change in momentum/ time |
Momentum before = momentum after |
Stopping distance = thinking distance + braking distance |
s=1/2 mv2/F |
Braking distance = kinetic energy/ Force |
Moment=Fs |
Moment = Force x distance from pivot |
P = F/A |
Pressure = Force/ Area |
P = hρg |
Pressure in a fluid = height x density x gravity |
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P6 - waves
v=fλ |
Velocity = frequency x wavelength |
T=1/f |
Period = 1/frequency |
Speed of light = 3x108m/s |
P7 - magnetism and electromagnetism
F=BIl |
Force on a conductor (at right angles to a magnetic field) carrying a current = magnetic flux density x current x length |
Vp/Vs= np/ns |
PD across primary coil/ PD across secondary coil = no of turns in primary coil/ no of coils in secondary coil |
VpIp=VsIs |
PD across primary coil x current across primary coil = PD across secondary coil x current across secondary coil |
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SI units and symbols
Acceleration |
m/s2 |
a |
Area |
m2 |
A |
Magnetic flux density |
Tesla (Vs/m2) |
B |
Specific heat capacity |
J/kgoC |
C |
Extension |
Metres (m) |
e |
Energy |
Joules (J) |
E |
Frequency |
Hertz (Hz) |
f |
Force |
Newtons (N) |
F |
Gravitational field strength |
N/kg |
g |
Height |
Metres (m) |
h |
Current |
Amps (A) |
I |
Spring constant |
Newtons per metre (N/m OR Nm-1) |
k |
Length |
m |
l |
Specific latent heat |
J/kg |
L |
Mass |
Kilograms (kg) |
m |
Moment |
Nm |
Moment |
Momentum |
kgm/s |
Momentum OR mv |
Pressure |
N/m2 |
P |
Power |
Watts (W) |
P |
Charge |
Coulombs (C) |
Q |
Resistance |
Ohms (Ω) |
R |
Displacement/ distance |
Metres (m) |
s |
Time |
Seconds (s) |
t |
Half-life |
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t1/2 |
Period |
s |
T |
Temperature |
Degrees celcius (oC) |
T |
Velocity/ speed |
Metres per second (m/s OR ms-1) |
v |
Volume |
m3 |
V |
Potential difference |
Volts (V) |
V |
Work done |
Nm OR J |
WD |
Weight |
Newtons (N) |
W OR mg |
Change in... |
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Δ |
Wavelength |
m |
λ |
Density |
kg/m3 |
ρ |
Activity |
Becquerels (Bq) |
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