Physics equations: AQA GCSE Physics

P1 Energy

Kinetic energy

Recall

Eₖ = ½mv²

kinetic energy = 0.5 × mass × (speed)²

Quantities in kinetic energy
Quantity	Symbol	Unit
kinetic energy	Eₖ	J
mass	m	kg
speed	v	m/s

Study notes for kinetic energy

Gravitational potential energy

Recall

Eₚ = mgh

g.p.e. = mass × gravitational field strength × height

Quantities in gravitational potential energy
Quantity	Symbol	Unit
gravitational potential energy	Eₚ	J
mass	m	kg
gravitational field strength	g	N/kg
height	h	m

Study notes for gravitational potential energy

Elastic potential energy

On the equation sheet

Eₑ = ½ke²

elastic potential energy = 0.5 × spring constant × (extension)²

Quantities in elastic potential energy
Quantity	Symbol	Unit
elastic potential energy	Eₑ	J
spring constant	k	N/m
extension	e	m

Study notes for elastic potential energy

Specific heat capacity

On the equation sheet

ΔE = mcΔθ

change in thermal energy = mass × specific heat capacity × temperature change

Quantities in specific heat capacity
Quantity	Symbol	Unit
change in thermal energy	ΔE	J
mass	m	kg
specific heat capacity	c	J/kg °C
temperature change	Δθ	°C

Study notes for specific heat capacity

Power from energy

Recall

P = E/t

power = energy transferred ÷ time

Quantities in power from energy
Quantity	Symbol	Unit
power	P	W
energy transferred	E	J
time	t	s

Study notes for power from energy

Power from work done

Recall

P = W/t

power = work done ÷ time

Quantities in power from work done
Quantity	Symbol	Unit
power	P	W
work done	W	J
time	t	s

Study notes for power from work done

Efficiency (energy)

Recall

efficiency = useful output energy transfer ÷ total input energy transfer

Quantities in efficiency (energy)
Quantity	Symbol	Unit
useful output energy transfer	–	J
total input energy transfer	–	J

Study notes for efficiency (energy)

Efficiency (power)

Recall

efficiency = useful power output ÷ total power input

Quantities in efficiency (power)
Quantity	Symbol	Unit
useful power output	–	W
total power input	–	W

Study notes for efficiency (power)

P2 Electricity

Charge flow

Recall

Q = It

charge flow = current × time

Quantities in charge flow
Quantity	Symbol	Unit
charge flow	Q	C
current	I	A
time	t	s

Study notes for charge flow

Potential difference, current and resistance

Recall

V = IR

potential difference = current × resistance

Quantities in potential difference, current and resistance
Quantity	Symbol	Unit
potential difference	V	V
current	I	A
resistance	R	Ω

Study notes for potential difference, current and resistance

Electrical power (pd and current)

Recall

P = VI

power = potential difference × current

Quantities in electrical power (pd and current)
Quantity	Symbol	Unit
power	P	W
potential difference	V	V
current	I	A

Study notes for electrical power (pd and current)

Electrical power (current and resistance)

Recall

P = I²R

power = (current)² × resistance

Quantities in electrical power (current and resistance)
Quantity	Symbol	Unit
power	P	W
current	I	A
resistance	R	Ω

Study notes for electrical power (current and resistance)

Energy transferred (power and time)

Recall

E = Pt

energy transferred = power × time

Quantities in energy transferred (power and time)
Quantity	Symbol	Unit
energy transferred	E	J
power	P	W
time	t	s

Study notes for energy transferred (power and time)

Energy transferred (charge and pd)

Recall

E = QV

energy transferred = charge flow × potential difference

Quantities in energy transferred (charge and pd)
Quantity	Symbol	Unit
energy transferred	E	J
charge flow	Q	C
potential difference	V	V

Study notes for energy transferred (charge and pd)

P3 Particle Model of Matter

Density

Recall

ρ = m/V

density = mass ÷ volume

Quantities in density
Quantity	Symbol	Unit
density	ρ	kg/m³
mass	m	kg
volume	V	m³

Study notes for density

Specific latent heat

On the equation sheet

E = mL

energy for a change of state = mass × specific latent heat

Quantities in specific latent heat
Quantity	Symbol	Unit
energy	E	J
mass	m	kg
specific latent heat	L	J/kg

Study notes for specific latent heat

Pressure and volume of a gas (Separate Physics only)

On the equation sheet

pV = constant

pressure × volume = constant (for a fixed mass of gas at a constant temperature)

Quantities in pressure and volume of a gas
Quantity	Symbol	Unit
pressure	p	Pa
volume	V	m³

Study notes for pressure and volume of a gas

P5 Forces

Weight

Recall

W = mg

weight = mass × gravitational field strength

Quantities in weight
Quantity	Symbol	Unit
weight	W	N
mass	m	kg
gravitational field strength	g	N/kg

Study notes for weight

Work done

Recall

W = Fs

work done = force × distance (moved along the line of the force)

Quantities in work done
Quantity	Symbol	Unit
work done	W	J
force	F	N
distance	s	m

Study notes for work done

Force on a spring

Recall

F = ke

force = spring constant × extension

Quantities in force on a spring
Quantity	Symbol	Unit
force	F	N
spring constant	k	N/m
extension	e	m

Study notes for force on a spring

Moment of a force (Separate Physics only)

Recall

M = Fd

moment = force × distance (perpendicular to the line of the force)

Quantities in moment of a force
Quantity	Symbol	Unit
moment	M	N m
force	F	N
distance	d	m

Study notes for moment of a force

Pressure (Separate Physics only)

Recall

p = F/A

pressure = force normal to a surface ÷ area of that surface

Quantities in pressure
Quantity	Symbol	Unit
pressure	p	Pa
force	F	N
area	A	m²

Study notes for pressure

Pressure in a liquid (Higher tier only) (Separate Physics only)

On the equation sheet

p = hρg

pressure = height of the column × density of the liquid × gravitational field strength

Quantities in pressure in a liquid
Quantity	Symbol	Unit
pressure	p	Pa
height of the column	h	m
density	ρ	kg/m³
gravitational field strength	g	N/kg

Study notes for pressure in a liquid

Distance, speed and time

Recall

s = vt

distance travelled = speed × time

Quantities in distance, speed and time
Quantity	Symbol	Unit
distance	s	m
speed	v	m/s
time	t	s

Study notes for distance, speed and time

Acceleration

Recall

a = Δv/t

acceleration = change in velocity ÷ time taken

Quantities in acceleration
Quantity	Symbol	Unit
acceleration	a	m/s²
change in velocity	Δv	m/s
time	t	s

Study notes for acceleration

Uniform acceleration

On the equation sheet

v² − u² = 2as

(final velocity)² − (initial velocity)² = 2 × acceleration × distance

Quantities in uniform acceleration
Quantity	Symbol	Unit
final velocity	v	m/s
initial velocity	u	m/s
acceleration	a	m/s²
distance	s	m

Study notes for uniform acceleration

Newton's second law

Recall

F = ma

resultant force = mass × acceleration

Quantities in newton's second law
Quantity	Symbol	Unit
resultant force	F	N
mass	m	kg
acceleration	a	m/s²

Study notes for newton's second law

Momentum (Higher tier only)

Recall

p = mv

momentum = mass × velocity

Quantities in momentum
Quantity	Symbol	Unit
momentum	p	kg m/s
mass	m	kg
velocity	v	m/s

Study notes for momentum

Force and change in momentum (Higher tier only) (Separate Physics only)

On the equation sheet

F = mΔv/Δt

force = mass × change in velocity ÷ time taken

Quantities in force and change in momentum
Quantity	Symbol	Unit
force	F	N
mass	m	kg
change in velocity	Δv	m/s
time taken	Δt	s

Study notes for force and change in momentum

P6 Waves

Wave speed

Recall

v = fλ

wave speed = frequency × wavelength

Quantities in wave speed
Quantity	Symbol	Unit
wave speed	v	m/s
frequency	f	Hz
wavelength	λ	m

Study notes for wave speed

Period

On the equation sheet

T = 1/f

period = 1 ÷ frequency

Quantities in period
Quantity	Symbol	Unit
period	T	s
frequency	f	Hz

Study notes for period

Magnification (Separate Physics only)

Recall

magnification = image height ÷ object height (no units)

Quantities in magnification
Quantity	Symbol	Unit
image height	–	same unit as the object
object height	–	mm or cm

Study notes for magnification

P7 Magnetism and Electromagnetism

Force on a conductor (Higher tier only)

On the equation sheet

F = BIl

force = magnetic flux density × current × length (at right angles to the field)

Quantities in force on a conductor
Quantity	Symbol	Unit
force	F	N
magnetic flux density	B	T
current	I	A
length	l	m

Study notes for force on a conductor

Transformer turns (Higher tier only) (Separate Physics only)

On the equation sheet

Vₚ/Vₛ = nₚ/nₛ

pd across primary ÷ pd across secondary = turns on primary ÷ turns on secondary

Quantities in transformer turns
Quantity	Symbol	Unit
pd across the primary coil	Vₚ	V
pd across the secondary coil	Vₛ	V
turns on the primary coil	nₚ	no unit
turns on the secondary coil	nₛ	no unit

Study notes for transformer turns

Transformer power (Higher tier only) (Separate Physics only)

On the equation sheet

VₚIₚ = VₛIₛ

pd across primary × current in primary = pd across secondary × current in secondary (100% efficient)

Quantities in transformer power
Quantity	Symbol	Unit
pd across the primary coil	Vₚ	V
current in the primary coil	Iₚ	A
pd across the secondary coil	Vₛ	V
current in the secondary coil	Iₛ	A

Study notes for transformer power

Physics equations

P1 Energy

Kinetic energy

Gravitational potential energy

Elastic potential energy

Specific heat capacity

Power from energy

Power from work done

Efficiency (energy)

Efficiency (power)

P2 Electricity

Charge flow

Potential difference, current and resistance

Electrical power (pd and current)

Electrical power (current and resistance)

Energy transferred (power and time)

Energy transferred (charge and pd)

P3 Particle Model of Matter

Density

Specific latent heat

Pressure and volume of a gas Physics only(Separate Physics only)

P5 Forces

Weight

Work done

Force on a spring

Moment of a force Physics only(Separate Physics only)

Pressure Physics only(Separate Physics only)

Pressure in a liquid Higher(Higher tier only) Physics only(Separate Physics only)

Distance, speed and time

Acceleration

Uniform acceleration

Newton's second law

Momentum Higher(Higher tier only)

Force and change in momentum Higher(Higher tier only) Physics only(Separate Physics only)

P6 Waves

Wave speed

Period

Magnification Physics only(Separate Physics only)

P7 Magnetism and Electromagnetism

Force on a conductor Higher(Higher tier only)

Transformer turns Higher(Higher tier only) Physics only(Separate Physics only)

Transformer power Higher(Higher tier only) Physics only(Separate Physics only)

Pressure and volume of a gas (Separate Physics only)

Moment of a force (Separate Physics only)

Pressure (Separate Physics only)

Pressure in a liquid (Higher tier only) (Separate Physics only)

Momentum (Higher tier only)

Force and change in momentum (Higher tier only) (Separate Physics only)

Magnification (Separate Physics only)

Force on a conductor (Higher tier only)

Transformer turns (Higher tier only) (Separate Physics only)

Transformer power (Higher tier only) (Separate Physics only)