UNIT 1: FORCES AND MOTION
Learn and apply:
distance travelled (m) = average speed (m/s) × time (s)
d=sxt
acceleration (m/s2) = change in velocity (m/s) ÷ time taken (s)
a = (v – u)
t
force (N) = mass (kg) × acceleration (m/s2)
F=m×a
weight (N) = mass (kg) × gravitational field strength (N/kg)
W=m×g
momentum (kgm/s) = mass (kg) × velocity (m/s)
p=m×v
moment (Nm) = force (N) x distance (m)
M=Fxd
Select and apply:
(final velocity)2 – (initial velocity)2 = 2 × acceleration × distance
(m)
(m/s)
(m/s)
(m/s2)
2
2
v –u =2×a×s
force (N) = change in momentum (kgm/s) ÷ time (s)
F = (mv – mu)
t
Edexcel iGCSE Physics Equations
UNIT 3: WAVES
Learn and apply:
wave velocity (m/s) = frequency (Hz) x wavelength (m)
v=fxλ
refractive index = angle of incidence(˚) ÷ angle of refraction(˚)
n = sin i
sin r
critical angle (˚) = 1 ÷ refractive index
sin c = 1
n
Select and apply:
Frequency (Hz) = 1 ÷ time period (s)
F= 1
T
UNIT 4: ENERGY RESOURCES AND ENERGY TRANSFER
Learn and apply:
Efficiency = (useful energy output ÷ total energy input) x 100
Efficiency = useful energy output x 100
total energy input
work done (J) = force (N) × distance (m)
W=Fxd
UNIT 2: ELECTRICITY
Learn and apply:
electrical power (W) = current (A) × potential difference (V)
P=IxV
gravitational potential energy (J)
= mass (kg) × gravitational field strength (N/kg) x height (m)
GPE = m × g × h
potential difference (V) = current (I) × resistance (Ω)
V=IxR
kinetic energy (J) = ½ × mass (kg) × (velocity)2 (m/s)
KE = ½ × m × v2
Energy transferred = work done
charge (C) = current (A) × time (s)
Q=Ixt
energy transferred (J)=charge moved (C) × potential difference (V)
E=Q×V
Select and apply:
energy transferred (J) =
current (A) × potential difference (V) × time (s)
E=IxVxt
Select and apply:
power (W) = work done (energy transferred) (J) ÷ time taken (s)
P=W
t
The equations in bold are Triple only – Paper 2.
LEARN all the equations from “Learn and apply”.
The equations from “Select and apply” will be given.
EVERY UNIT needs to be learned – these are in brackets and will
NOT be given in an exam.
UNIT 5: SOLIDS, LIQUIDS AND GASES
Learn and apply:
density (kg/m3) = mass (kg) ÷ volume (m3)
ρ=m
V
pressure (N/m2 or Pa) = force (N) ÷ area (m2)
P = F
A
pressure difference (Pa) =
height (m) × density (kg/m3) × gravitational field strength (N/kg)
P=h×ρ×g
Select and apply:
change in thermal energy (J)=
mass (kg) × specific heat capacity (J/kg˚C) × change in temperature (˚C)
ΔQ = m × c × ΔT
To calculate pressure and Kelvin temperature of a fixed mass of gas at
a constant temperature (Pressure in Pa; Temp in ˚C)
P1 = P2
T1 T2
To calculate pressure or volume for gases of fixed mass at constant
temperature
P1 x V1 = P2 x V2 (Pressure in Pa; Volume in m3)
UNIT 6: MAGNETISM
Learn and apply:
voltage across primary coil (V) = number of turns in primary coil
voltage across secondary coil (V) number of turns in secondary
Vp = Np
Vs Ns
(pd × current) in primary coil = (pd × current) in secondary coil
(valid only where there is 100% efficiency)
Vp × Ip = Vs × Is (p.d. in V; current in A)
UNIT 8: ASTROPHYSICS
Select and apply:
orbital speed (km/s or m/s) = 2 x π x orbital radius (m or km) ÷ time (s)
v=2xπxr
T
change in wavelength (km or m) = velocity of a galaxy (m/s)
reference wavelength (km or m)
speed of light (m/s)
λ – λ0 = Δλ = v
λ0
λ0 c
UNIT 1: FORCES AND MOTION
Learn and apply:
distance travelled (m) = average speed (m/s) × time (s)
d=sxt
acceleration (m/s2) = change in velocity (m/s) ÷ time taken (s)
a = (v – u)
t
force (N) = mass (kg) × acceleration (m/s2)
F=m×a
weight (N) = mass (kg) × gravitational field strength (N/kg)
W=m×g
momentum (kgm/s) = mass (kg) × velocity (m/s)
p=m×v
moment (Nm) = force (N) x distance (m)
M=Fxd
Select and apply:
(final velocity)2 – (initial velocity)2 = 2 × acceleration × distance
(m)
(m/s)
(m/s)
(m/s2)
2
2
v –u =2×a×s
force (N) = change in momentum (kgm/s) ÷ time (s)
F = (mv – mu)
t
Edexcel iGCSE Physics Equations
UNIT 3: WAVES
Learn and apply:
wave velocity (m/s) = frequency (Hz) x wavelength (m)
v=fxλ
refractive index = angle of incidence(˚) ÷ angle of refraction(˚)
n = sin i
sin r
critical angle (˚) = 1 ÷ refractive index
sin c = 1
n
Select and apply:
frequency (Hz) = 1 ÷ time period (s)
F= 1
T
UNIT 4: ENERGY RESOURCES AND ENERGY TRANSFER
Learn and apply:
efficiency = (useful energy output ÷ total energy input) x 100
Efficiency = useful energy output x 100
total energy input
work done (J) = force (N) × distance (m)
W=Fxd
UNIT 2: ELECTRICITY
Learn and apply:
electrical power (W) = current (A) × potential difference (V)
P=IxV
potential difference (V) = current (I) × resistance (Ω)
V=IxR
charge (C) = current (A) × time (s)
Q=Ixt
energy transferred (J)=charge moved (C) × potential difference (V)
E=Q×V
Select and apply:
energy transferred (J) =
current (A) × potential difference (V) × time (s)
E=IxVxt
gravitational potential energy (J)
= mass (kg) × gravitational field strength (N/kg) x height (m)
GPE = m × g × h
kinetic energy (J) = ½ × mass (kg) × (velocity)2 (m/s)
KE = ½ × m × v2
Energy transferred = work done
Select and apply:
power (W) = work done (energy transferred) (J) ÷ time taken (s)
P=W
t
The equations in bold are Triple only – Paper 2.
LEARN all the equations from “Learn and apply”.
The equations from “Select and apply” will be given.
EVERY UNIT needs to be learned – these are in brackets and will
NOT be given in an exam.
UNIT 5: SOLIDS, LIQUIDS AND GASES
Learn and apply:
density (kg/m3) = mass (kg) ÷ volume (m3)
ρ=m
V
pressure (N/m2 or Pa) = force (N) ÷ area (m2)
P = F
A
pressure difference (Pa) =
height (m) × density (kg/m3) × gravitational field strength (N/kg)
P=h×ρ×g
Select and apply:
change in thermal energy (J)=
mass (kg) × specific heat capacity (J/kg˚C) × change in temperature (˚C)
ΔQ = m × c × ΔT
To calculate pressure and Kelvin temperature of a fixed mass of gas at
a constant temperature (Pressure in Pa; Temp in ˚C)
P1 = P2
T1 T2
To calculate pressure or volume for gases of fixed mass at constant
temperature
P1 x V1 = P2 x V2 (Pressure in Pa; Volume in m3)
UNIT 6: MAGNETISM
Learn and apply:
voltage across primary coil (V) = number of turns in primary coil
voltage across secondary coil (V) number of turns in secondary
Vp = Np
Vs Ns
(pd × current) in primary coil = (pd × current) in secondary coil
(valid only where there is 100% efficiency)
Vp × Ip = Vs × Is (p.d. in V; current in A)
UNIT 8: ASTROPHYSICS
Select and apply:
orbital speed (km/s or m/s) = 2 x π x orbital radius (m or km) ÷ time (s)
v=2xπxr
T
change in wavelength (km or m) = velocity of a galaxy (m/s)
reference wavelength (km or m)
speed of light (m/s)
λ – λ0 = Δλ = v
λ0
λ0 c