Physics Equations
These
are all of the equations you used to need to recall for Physics examinations...
at each stage it was assumed you remembered the ones from the previous
stage... so it was worth transferring them properly to your mental 'hard
drive'!
The English examination boards now GIVE you equations  so you no longer get marks for recalling them. However, I would argue that actually knowing them makes it easier for you to explain a physics principle.
For example if you KNOW that F=ma, then, in answer to, 'What comprises evedence of a force acting?', you know that a net force will make a body accelerate.
Having a mathematical mind myself I find learning equations to be a shorthand way of learning Physics!
Make
sure you know the correct units.......... all units to be used in equations should be in their basic form (no prefixes)  EXCEPT mass  that is kg!
Remember
to take care when you write the equation letters... they are symbols
NOT part of your handwriting!
Special care with
I
for current it shouldn't be possible to confuse it with
l
for
length or 1 (the number one)!
Equation
in words

Symbolic
representation

Year 
Key
Stage 
speed
= distance travelled
time taken

v
= d/t 
Y7 
KS3 
acceleration =
change in velocity
time taken

a
= Dv/t 
Y8 
KS3 
density
= mass
volume

r
= m/V 
Y7 
KS3 
force
= mass x acceleration 
F
= ma 
Y9 
KS3 
work
done = force x distance moved in the direction of that force 
W
= Fs 
Y9 
KS3 
momentum
= mass x velocity 
p
= mv 
Y12 
AS 
power
= energy transferred
time taken

P
= E/t 
Y8 
KS3 
power
= work done
time taken

P
= W/t 
Y9 
KS3 
weight
= mass x gravitational field
strength 
w
= mg 
Y7 
KS3 
kinetic
energy = half x mass x (velocity squared) 
E_{K}=
^{1}/_{2}mv^{2} 
Y12 
KS4 
change
in gravitational potential energy = mass x gravitational field
strenth x difference in height 
DGPE
= mgDh 
Y9 
KS3 
pressure
= force applied
contact area 
P
= F
A 
Y7 
KS3 
Gas
Law: pressure x volume of a gas = number of moles x molar
gas constant x absolute temperature 
pV
= nRT 
Y12 
AS 
Gas
Law: combination of Boyle's Law and Charles' Law 
P_{1}V_{1}
= P_{2}V_{2}
T_{1} T_{2}
_{NB
Temperature MUST be in Kelvin}

Y11 
KS4 
charge
= current x time 
DQ
= IDt 
Y10 
KS4 
Ohm's
Law: Potential difference = current x resistance 
V
= IR 
Y8 
KS3 
Ohm's
Law applied to the full circuit: Electromotive force = current
x (sum of the circuit resistance and the internal resistance of
the cell) 
EMF
= I(R
+ r) 
Y12 
AS 
power
= current x potential difference 
P
= I V 
Y8 
KS3 
energy
transferred in a component = charge passing through it x potential
difference acorss it 
W
= QV 
Y10 
KS4 
resistance
= resistivity x length
cross sectional area 
R
= r l
A 
Y12 
AS 
wavespeed
= frequency x wavelength 
v
= fl
for electromagnetic
radiation v = c giving:
c = fl 
Y8 
KS3 
centripetal
force = mass x speed^{2}
radius of path 
F_{C}
= mv^{2}
r 
Y13 
A2 
Electrical
energy changed into heat = potential difference x current x time 
E
= VI t 
Y9 
KS3 
Inverse
square law for force on a mass in a gravitational field of
another mass: Force is proportional to the product of the masses
and inversely proportional to the square of the distance between
them 
F_{G}
=  G m_{1} m_{2}
r^{2}
NB the
minus sign indicates it is ALWAYS attractive

Y13 
A2 
Inverse
square law for force on a charge in an electric field of another
charge: Force is proportional to the product of the charges and
inversely proportional to the square of the distance between them 
F_{E}= 1 Q_{1} Q_{2}
4pe0 r^{2}
NB the
overall sign indicating wherther it is attractive (negative)
or repulsive (positive) comes from the signs of the charges.
Also, although the constant
of proportionality is complex it is a similar relationship to
above.

Y13 
A2 
capacitance
= charge stored
potential difference 
C =
Q
V 
Y13 
A2 
ratio
of the voltages across the coils of a transformer = the ratio
of the turns on the coils 
V1
= N1
V2 N2
NB the 1 could be P
for primary and the 2 could be s for secondary  it doesn't matter
which is which! 
Y11 
KS4 
LOJ November 2000/revised
October 2001/revised November 2002 and November 2010