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Physics Data Booklet: Formulas & Constants for Exams

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Physics data booklet
For use during the course and in the examinations
First assessment 2025
Version 1.1
Annotated by YPhysics (Version 1.0)
Contents
Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Mathematical equations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Uncertainties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Fundamental constants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Metric (SI) multipliers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Unit conversions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Electrical circuit symbols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Electromagnetic spectrum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
A. Space, time and motion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
B. The particulate nature of matter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
C. Wave behaviour . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
D. Fields . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
E. Nuclear and quantum physics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Physics data booklet
Mathematical equations
1
(bh ) where b is the base, h is the height
2
Area of a triangle
A
Area of a circle
A = πr 2 where r is the radius
Circumference of a circle
C = 2πr
Volume of a cuboid
V lwh where l is the length, w is the width, h is the
height
Volume of a cylinder
V
r 2h
Volume of a prism
V
Ah where A is the area of cross-section
Volume of a sphere
V=
4 3
πr
3
Area of the curved surface
of a cylinder
A
2 rh
Vectors
A
AV
θ
Trigonometric relationships
AH
A cos
AV
A sin
tan θ =
AH
sin θ
cos θ
sin2 θ + cos2 θ = 1
2
Physics data booklet
Uncertainties
If: y = a ± b
If: y
If: y
then: ∆y = ∆a + ∆b
ab
c
∆y ∆a ∆b ∆c
=
+
+
then:
y
a
b
c
an
then:
∆y
∆a
= n
y
a
Δy: absolute/raw uncertainty in y
y: value of y
Δa: absolute/raw uncertainty in a
a: value of a
Δb: absolute/raw uncertainty in b
b: value of b
Δc: absolute/raw uncertainty in c
c: value of c
Fundamental constants
Quantity
Symbol
Approximate value
Acceleration of free fall
g
9.8 m s2 (Earth’s surface)
Gravitational constant
G
6.67 × 10−11 Nm2 kg−2
Avogadro constant
NA
6.02 × 1023 mol−1
Gas constant
R
8.31JK 1 mol1
Boltzmann constant
kB
1.38 × 10−23 JK −1
Stefan–Boltzmann constant
V
5.67 × 10−8 W m−2 K −4
Coulomb constant
k
8.99 × 109 Nm2 C−2
Permittivity of free space
H0
8.85 × 10−12 C2 N−1 m−2
4π × 10−7 T mA −1
Permeability of free space
Speed of light in vacuum
c
3.00 × 108 m s−1
Planck constant
h
6.63 × 10−34 Js
Elementary charge
e
1.60 × 10−19 C
Electron rest mass
me
9.110 × 10−31 kg = 0.000549 u = 0.511MeV c −2
Proton rest mass
mp
1.673 × 10−27 kg = 1.007276 u = 938 MeV c −2
Neutron rest mass
mn
1.675 × 10−27 kg = 1.008665 u = 940 MeV c −2
(Unified) atomic mass unit
u
1.661× 10−27 kg = 931.5 MeV c −2
Solar constant
S
1.36 × 103 W m−2
Fermi radius
R0
1.20 × 10−15 m
Physics data booklet
3
Metric (SI) multipliers
Prefix
Abbreviation
Value
peta
P
1015
tera
T
1012
giga
G
109
mega
M
106
kilo
k
103
hecto
h
102
deca
da
101
deci
d
101
centi
c
102
milli
m
103
micro
μ
106
nano
n
109
pico
p
1012
femto
f
1015
Unit conversions
1 radian (rad) ≡
180°
π
Temperature (K ) = temperature ( °C ) + 273
1 light year ( ly ) = 9.46 × 1015 m
1 parsec (pc ) = 3.26 ly
1 astronomical unit ( AU) = 1.50 × 1011 m
1 kilowatt-hour ( kWh ) = 3.60 × 106 J
h c = 1.99 × 10−25 Jm = 1.24 × 10 −6 eV m
4
Physics data booklet
Electrical circuit symbols
Cell
Battery
Switch
Voltmeter
Ammeter
Resistor
Variable resistor
Light-dependent resistor
(LDR)
Thermistor
Potentiometer
Lamp
Light emitting diode (LED)
Heating element
Motor
Earth (ground)
Electromagnetic spectrum
energy
10 16
10 14
Jrays
10 12
10 10
10 8
X-rays
UV
10 6
IR
10 4
10 2
microwaves
100
102
10 4
106
108 wavelength / m
radio waves
V I B G Y O R
400
700
wavelength / nm
Physics data booklet
5
A. Space, time and motion
Standard level and higher level
A.1 Kinematics
s=
s: displacement
u: initial velocity
v: final velocity
a: acceleration
t: time
u +v
t
2
v = u + at
s = ut +
(Use + or - to include direction)
1 2
at
2
v 2 = u 2 + 2as
A.2 Forces and momentum
Ff ≤ µsFN
FH: elastic force from helical spring (Hooke’s Law)
k: spring’s constant
x: extension or compression of spring
Ff = µdFN
Fb: buoyant force (upthrust)
ρ: density of fluid
V: volume submerged in fluid
g: acceleration of free fall
p: momentum
m: mass
v: velocity
F: resultant/net force
m: mass
a: acceleration
Δp: change in momentum (Δp=mv-mu)
Δt: time taken
A.3 Work, energy and power
FH = −k x
Fd = 6πη rv
Fb = ρVg
Fg
mg
p
mv
Fg: gravitational force (weight close to Earth’s surface)
m: mass
g:acceleration of free fall
J = F ∆t
F = ma =
Fd: drag force (resistive force from fluids)
η: coefficient of viscosity
r: radius
v: speed
∆p
∆t
J: impulse
F: force
Δt: time taken
a=
v2
4π 2 r
= ω 2r = 2
r
T
v=
2π r
= ωr
T
W = Fs cos θ
Ek: kinetic energy
m: mass
v: speed
p: momentum
EH: elastic potential energy stored in helical spring
k: spring’s constant
Δx : extension or compression of the spring
P: Power
ΔW: work done / energy transferred
Δt: time taken
F: average force
v: average speed
η: efficiency
6
Ff: frictional force (friction)
μs: coefficient of static friction
μd: coefficient of dynamic friction
FN: normal contact force
1
p2
mv 2 !
2
2m
Ek !
∆Ep = mg ∆h
EH =
1
k ∆x 2
2
a: centripetal acceleration
v: linear speed
r: radius
T: period
ω: angular speed
W: work done by force F
F: force
s: displacement of point of action of force F
θ: angle between direction of F and direction of s
ΔΕp: change in gravitational potential energy
m: mass
g: acceleration of free fall
Δh: change in height
P=
∆W
= Fv
∆t
η=
useful work out useful power out
=
total work in
total power in
Physics data booklet
Additional higher level
A.4 Rigid body mechanics
τ = Fr sin θ
∆θ =
Δθ: angular displacement
ωf: final angular velocity
ωi: initial angular velocity
a: angular acceleration
t: time
(use + and - to include direction )
I: moment of inertia
m: mass
r: distance from point or axis of rotation
2
(Note: Σ means sum i.e Σmr 2= m1r12 + m2r2 + m3r32 + …)
L: angular momentum
I: moment of inertia
ω: angular velocity
ΔL: change in angular momentum
I: moment of inertia
ω: angular velocity
A.5 Galilean and special relativity
x’:position of an event in an inertial frame of reference moving
with relative speed v to the original frame of reference
x:position of the same event in the original frame of reference
v: relative speed between the two inertial frames of reference
t’: time of an event in an inertial frame of reference moving with
relative speed v to the original frame of reference
t: time of the same event in the original frame of reference
u’: velocity of body in n inertial frame of reference moving with
relative speed v to the original frame of reference
τ: torque
F: force
r: distance from axis to point of action of F
θ: angle between direction of F and direction of r
ωf + ωi
t
2
ωf = ωi + α t
1
∆θ = ωit + α t 2
2
ωf2 = ωi2 + 2α∆θ
I = Σmr 2
τ = Iα
L = Iω
∆L = τ∆t
τ: resultant/net torque
I: moment of inertia
a: angular acceleration
ΔL: change in angular momentum
τ: resultant/net torque
Δt: time taken
∆L = ∆( I ω )
Ek =
1 2 L2
Iω =
2
2I
x ' = x − vt
t'
t
u' = u −v
x ' = γ ( x − vt ) where γ =
u' =
u −v
uv
1− 2
c
( ∆s )2 = (c ∆t )2 − ∆x 2
c: speed of light in vacuum (constant)
∆t = γ∆t0
Δto: proper time (time interval measured by same clock)
v2
c2
 vx 
t ' = γ t − 2 
c 

γ: the Lorrentz factor
γ: the Lorrentz factor
1
1−
u: velocity of the same body in the original frame of reference
Δt: time interval between two observed events (2
different clocks)
Ek: rotational kinetic energy
I: moment of inertia
ω: angular speed
L: angular momentum
L=
L0
γ
tan θ =
v
c
Δs: space-time interval between two
events
c: speed of ligh
Δt: time interval
Δx: distance between the events
L: observed length
Lo: proper length
γ: the Lorrentz factor
θ: angle of worldline from the vertical axis in a space-time diagram
v: speed of the body
Physics data booklet
7
B. The particulate nature of matter
Standard level and higher level
B.1 Thermal energy transfers
Ek: average random kinetic energy of
particles
kB: Boltzmann constant
T: temperature
ΔQ: amount of heat (energy) transfer
Δt: time taken
k: thermal conductivity of material
A: surface area of the surface that emits heat
ΔT: temperature difference between hot and cold sides
Δx: thickness (distance between hot and cold sides)
ρ=
m
V
Ek
3
kBT
2
ρ: density
m: mass
V: volume
Q: heat (energy transferred)
m: mass
c: specific heat capacity
L: specific latent heat
ΔΤ: change in temperature
Q = mc ∆T
Q
mL
∆Q
∆T
= kA
∆t
∆x
L: luminosity (total power output)
σ: Steffan-Boltzmann constant
A: surface area of body
T: temperature
L = σ AT 4
b: brightness (intensity)
L: luminosity
d: distance from the source
b=
L
4π d 2
λmax: peak wavelength
T: temperature
λmaxT = 2.9 × 10−3 mK
B.2 Greenhouse effect
σ: Steffan-Boltzmann constant
T : temperature
emissivity =
albedo
B.3 Gas laws
n: number of moles
N: number of particles (atoms or molecules)
NA: Avogadro constant
P: pressure
ρ: density of gas
v: root mean square speed of particles (r.m.s speed)
8
P
F
A
n
N
NA
power radiated per unit area
σT 4
total scattered power
total incident power
P: pressure
F: force
A: area
PV
T
constant
PV
nRT
P=
1 2
ρv
3
U
3
nRT
2
NkBT
P: pressure
V: volume
T: temperature
N:number of moles
R: gas constant
N: number of particles
KB: Boltzmann constant
U: internal energy of gas
3
NkBT
2
Physics data booklet
B.5 Current and circuits
V: potential difference
W: work done
q: charge
ρ: resistivity
R: resistance
A: cross-sectional area
L: length
P: power
I: current
V: potential difference
R: resistance
I=
∆q
∆t
V
W
q
R
V
I
ρ=
RA
L
P
IV
R: resistance
V: potential difference
I: current
I R
2
V2
R
Series circuits
Parallel circuits
...
I = I1 + I 2 + ...
I
ε: electromotive force (emf)
I: current
R: resistance of connected circuit
r: internal resistance
I:current
Δq: amount of charge passing through a surface
Δt: time taken
I1
I2
V = V1 + V2 + ...
V
Rs = R1 + R2 + ...
1
1
1
=
+
+ ...
Rp R1 R2
V1 V2
...
ε = I(R + r )
Additional higher level
B.4 Thermodynamics
W: work done by gas
P: pressure
ΔV: change in volume
ΔS: change in entropy
ΔQ: amount of thermal energy (heat) that flows into a body
T: temperature
S: entropy
kB: Boltzmann constant
Ω: number of possible micro states of the system
Q = ∆U + W
W = P ∆V
∆U =
3
3
nR ∆T = NkB ∆T
2
2
∆S =
∆Q
T
Physics data booklet
ΔU: change in internal energy of a gas
n: number of moles
R: Gas constant
ΔΤ: change in temperature
N: number of atoms
kB: Boltzmann constant
S = kB ln Ω
PV
η: efficiency
ηCarnot: efficiency of a Carnot cycle
Tc: temperature of cold gas
Th: temperature of hot gas
Q: amount of thermal energy (heat)
ΔU: change in internal energy
W: work done by the gas
η=
5
3
constant
useful work
input energy
ηCarnot = 1 −
(Model for adiabatic processes)
P: Pressure of monatomic ideal gas
V: Volume of monatomic ideal gas
Tc
Th
9
C. Wave behaviour
Standard level and higher level
C.1 Simple harmonic motion
Τ: period
f : frequency
ω: angular frequency
T: period of simple pendulum
l: length
g: acceleration of free fall (constant)
a = −ω 2 x
T =
a: acceleration
ω: angular frequency
×: displacement from equilibrium position
1 2π
=
f
ω
T = 2π
m
k
T = 2π
l
g
T: period of a mass-spring system
m: mass
k: spring’s constant
λ
T
C.2 Wave model
v= fλ =
C.3 Wave phenomena
n1 sin θ 2 v 2
=
=
n2 sin θ1 v1
n1: refractive index of medium 1
n2: refractive index of medium 2
θ1: angle of incidence
θ2: angle of refraction
v1: speed of wave in medium 1
v2: speed of wave in medium 2
s: distance between adjacent maxima
λ: wavelength
D: distance between slits and screen
d: distance between slits
C.5 Doppler effect
v: wave speed
f : frequency
λ: wavelength
Constructive interference:
path difference = nλ
Destructive interference:
1
path difference = (n + )λ
2
λD
d
∆f ∆λ v
=
≈
f
λ
c
s=
Additional higher level
C.1 Simple harmonic motion
x: displacement from equilibrium position
xo: amplitude
ω: angular frequency
t: time
φ: initial phase
v: velocity
ET: total energy of simple harmonic oscillator
Ep: potential energy of simple harmonic oscillator
m: mass
10
n= 0, 1, 2, 3, …
λ: wavelength
Δf : change/shift in frequency
f : frequency of emitted wave
Δλ: change/shift in wavelength
λ: wavelength of emitted wave
v: relative speed between source and observer
c: speed of light (constant)
x = x0 sin(ωt + φ )
v = ω x0 cos(ωt + φ )
v = ±ω x0 2 − x 2
ET =
1
mω 2 x02
2
Ep =
1
mω 2 x 2
2
Physics data booklet
΄
θ: angle at which first diffraction minimum appears
λ: wavelength
b: slit width
C.3 Wave phenomena
θ=
λ
b
nλ = d sin θ
C.5 Doppler effect
n: order (1, 2, 3, … )
λ: wavelength
d: distance between slits of diffraction grating
θ: angle at which this order minimum will appear

v 

 v ± us 
Moving source: f ′ = f 
 v ± uo 
Moving observer: f ′ = f 

 v 
Physics data booklet
f ΄ :observed frequency
f : emitted frequency
v: wave speed
uo: speed of observer
us: speed of source
11
F: gravitational force
G: gravitational constant
m1: mass of body 1
m2: mass of body 2
r: distance between the centres of the 2 bodies
D. Fields
Standard level and higher level
D.1 Gravitational fields
D.2 Electric and magnetic fields
F: electric field force between two charged particles
k: Coulomb’s constant
εο: permittivity of free space (constant)
q1: charge of particle 1
q2: charge of particle 2
D.3 Motion in electromagnetic fields
F: magnetic force on moving charged particle
q: charge of particle
v: speed of particle
B: magnetic field strength
θ: angle between magnetic field lines and direction of speed
F
G
m1m2
r2
g
F
m
G
F
k
E
F
q
E
V
d
M
r2
q1q2
1
where k =
2
4πε 0
r
Ep: gravitational potential energy
G: gravitational constant
m1: mass of body 1
m2: mass of body 2
r: distance between the centres of bodies
F = qvB sin θ
F = B I L sin θ
II
F
= µ0 1 2
2π r
L
Ep = −G
m1m2
r
Vg = −G
M
r
g=−
g: gravitational field strength
ΔVg: change in the gravitational potential between two points
Δr: distance between the two points
W: work done to move a mass in a gravitational field
m: mass of body that is moving
ΔVg: change in the gravitational potential between two points
D.2 Electric and magnetic fields
Ve: electric potential at a point in an electric field
k: Coulomb’s constant
Q: charge creating the field
r: distance between point and centre of charge
E: electric field strength
ΔV: electric potential difference between two points in the field
Δr: distance between the points
12
∆Vg
∆r
W = m∆Vg
v esc
2GM
r
v orbital
GM
r
q1q2
r
Ep
k
Ve
kQ
r
E=−
E: electric field strength
F: electric field force
q: charge
E: electric field strength of a uniform electric field
V: potential difference between two points (or metal plates)
d: distance between the two points (or metal plates)
Additional higher level
D.1 Gravitational fields
g: gravitational field strength
F: gravitational force
m: mass
G: gravitational constant
M: mass of the body that creates the gravitational field
r: distance from the centre of that body
∆Ve
∆r
W = q ∆Ve
F: magnetic force on current currying wire
B: magnetic field strength
I: current
L: length of wire in the magnetic field
θ: angle between magnetic field lines and current
F: magnetic force between current currying wire
L: length of wire
μο: permeability of free space (constant)
I1: current in wire 1
I2: current in wire 2
r: distance between wires
Vg: gravitational potential at a point in a gravitational field
G: gravitational constant
M: mass of the body creating the field
r: distance of the point from the centre of the body.
vesc: speed needed to escape a gravitational field
vorbital: orbital speed
G: gravitational constant
M: mass of body creating the gravitational field
r: distance from the centre of that body
Ep: electric potential energy
k: Coulomb’s constant
q1: charge on body 1
q2: charge on body 2
r: distance between the centres of the bodies
W: work done to move a charge in an electric field
q: charge moved
ΔVe: electric potential difference between the points
Physics data booklet
Φ: magnetic flux
B: magnetic field strength
A: area
θ: angle between magnetic field lines and the perpendicular direction to the surface
D.4 Induction
ε: induced emf
N: number of loops on coil
ΔΦ: change in magnetic flux
Δt: time taken
Φ = BA cos θ
ε = −N
∆Φ
∆t
ε: emf induced across the ends of a straight conductor
moving in a magnetic field
ε = BvL
B: magnetic field strength
v: speed of conductor
l: length of conductor in field
E. Nuclear and quantum physics
E: energy of a photon
h: Planck’s constant
f : frequency
Standard level and higher level
E.1 Structure of the atom
E
hf
E.3 Radioactive decay
E
mc 2
E.5 Fusion and stars
E: energy released
m: mass ‘loss’ (change in mass)
c: speed of light (constant)
d(parsec)
1
p(arc-second)
d: distance to star
p: parallax angle
Additional higher level
E.1 Structure of the atom
E: energy value of energy level
n: quantum number of energy level (n= 1,2,3,..)
(eV is just the unit, energy here is calculated in electrovolts)
R
1
R0 A 3
E=−
13.6
eV
n2
R: radius of atom
Ro: Fermi radius (constant)
A: atomic number (number of protons)
mvr: angular momentum
m: mass
v: linear speed
r: radius of circular path
n: quantum number (n=1,2,3,4,…)
h: Planck’s constant
nh
mvr =
2π
E.2 Quantum physics
Emax: maximum kinetic of energy of emitted electrons
h: Planck’s constant
f: frequency of incident radiation
Φ: work function of metal surface
E.3 Radioactive decay
N: number of nuclei left after time t
No: original number of nuclei in the sample (at t=0)
λ: decay constant of material
t: time
A: activity (number of decays per second)
T1/2: half-life
Physics data booklet
Emax = h f − Φ
λ=
h
p
λf − λi = ∆λ =
h
(1 − cos θ )
me c
N = N0 e − λ t
A = λ N = λ N0 e − λ t
T1 =
2
ln 2
λ
λ: wavelength
h: Planck’s constant
p: momentum
λf: final wavelength
λi: initial wavelength
Δλ: change in wavelength
h: Planck’s constant
me: mass of electron (constant)
c: speed of light in vacuum (constant)
θ: scattering angle
13
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