9702

Times Edu Press

Cambridge International

A Level
Physics9702

AS Level · A2 Level · Full Syllabus

AS Level · Papers 1–3 A2 Level · Papers 4–5

19Topics

50+Formulas

Song ngữAnh – Việt

Overview

Giới thiệu A Level Physics 9702

Cambridge International A Level Physics (9702) gồm AS Level (năm 1, Papers 1–3) và A2 Level (năm 2, Papers 4–5).

Paper	Level	Type	Duration	Marks
Paper 1	AS	Multiple Choice (MCQ)	1h 15m	40
Paper 2	AS	Structured questions	1h 15m	60
Paper 3	AS	Practical examination	2h	40
Paper 4	A2	Structured questions	2h	100
Paper 5	A2	Planning & Analysis	1h 15m	30

★

Mẹo thi Physics 9702

Học thuộc DEFINITIONS — nhiều câu 1–2 marks hỏi định nghĩa chính xác
Trình bày đơn vị (units) ở mỗi bước tính toán
Sig figs: Dùng 2–3 significant figures phù hợp với dữ liệu cho trước
Formula booklet được cung cấp — phải biết cách tra và áp dụng nhanh
Vẽ đồ thị: Tiêu đề trục có đơn vị, điểm rải đều, best-fit line thẳng/cong phù hợp

AS · Topic 1

Physical Quantities & Units

SI Base Units

Quantity	Đại lượng	SI Unit	Symbol
Mass	Khối lượng	kilogram	kg
Length	Độ dài	metre	m
Time	Thời gian	second	s
Current	Dòng điện	ampere	A
Temperature	Nhiệt độ	kelvin	K
Amount of substance	Số mol	mole	mol

Prefixes

T = 10¹² (tera)

G = 10⁹ (giga)

M = 10⁶ (mega)

k = 10³ (kilo)

c = 10⁻² (centi)

m = 10⁻³ (milli)

μ = 10⁻⁶ (micro)

n = 10⁻⁹ (nano)

p = 10⁻¹² (pico)

Scalar vs Vector

Classification

Scalar (độ lớn only): mass · speed · energy · time · temperature · distance · power

Vector (độ lớn + hướng): force · velocity · acceleration · displacement · momentum · weight

Cộng vectors: Fₓ = F cosθ · Fy = F sinθ · Parallelogram rule

Errors & Uncertainties

Uncertainty Rules

Add/Subtract: Cộng absolute uncertainties: Δ(A±B) = ΔA + ΔB

Multiply/Divide: Cộng % uncertainties: %Δ(AB) = %ΔA + %ΔB

Power n: Nhân % uncertainty × n: %Δ(xⁿ) = n × %Δx

AS · Topic 2

Kinematics

SUVAT Equations (constant acceleration only)

v = u + at

s = ut + ½at²

v² = u² + 2as

s = ½(u + v)t

Free fall: u = 0, a = g = 9.81 m/s² (downward)

Graphs: s–t: gradient = v · v–t: gradient = a, area = s

Worked Example

AS · Topic 2

VD1 · Projectile — Max height

Đạn bắn lên với u = 30 m/s. Tìm độ cao cực đại.

✓ Solution

Tại độ cao max: v = 0

v² = u² + 2as
0 = (30)² + 2(−9.81)s
0 = 900 − 19.62s
s = 900 / 19.62 = 45.9 m

AS · Topic 3

Dynamics

Newton's Laws & Momentum

N1: ∑F = 0 → a = 0 (equilibrium)

N2: ∑F = ma · F = Δp/Δt

N3: Fₐᵦ = −Fᵦₐ (same type, opposite direction, different objects)

p = mv

Δp = FΔt (impulse)

Conservation: m₁u₁ + m₂u₂ = m₁v₁ + m₂v₂

Elastic: Conserve p AND KE · Relative speed: u₁−u₂ = v₂−v₁

Inelastic: Conserve p only · KE NOT conserved

Worked Example

AS · Topic 3

VD2 · Elastic collision

2 kg (u = 6 m/s) va chạm đàn hồi với 4 kg (đứng yên). Tìm v₁, v₂.

✓ Solution

Conservation of momentum:
2(6) + 4(0) = 2v₁ + 4v₂
12 = 2v₁ + 4v₂  ... (1)

Elastic → relative speed unchanged:
u₁ − u₂ = v₂ − v₁
6 − 0 = v₂ − v₁
v₂ = v₁ + 6  ... (2)

Sub (2) into (1):
12 = 2v₁ + 4(v₁ + 6) = 6v₁ + 24
v₁ = −2 m/s  (bounces back)
v₂ = 4 m/s

AS · Topic 4

Forces, Density & Pressure

Forces, Pressure & Moments

ρ = m / V

p = F / A

Δp = ρgΔh

Upthrust = weight of fluid displaced

Moment = F × d⊥

Torque of couple = F × d

Equilibrium: ∑F = 0 AND ∑Moments = 0

AS · Topic 5

Work, Energy & Power

Energy & Power Formulas

W = Fs cosθ

KE = ½mv²

GPE = mgh

Elastic PE = ½kx²

P = W/t = Fv

Efficiency = (useful output / total input) × 100%

Worked Example

AS · Topic 5

VD3 · Braking distance

Ô tô 1200 kg, v = 30 m/s. Phanh với lực 4000 N. Tìm quãng đường dừng.

✓ Solution

KE = ½mv² = ½(1200)(30²) = 540 000 J

Work done by braking force = KE lost:
W = Fs → 540 000 = 4000 × s
s = 540 000 / 4000 = 135 m

AS · Topic 6

Deformation of Solids

Stress, Strain & Young Modulus

F = kx (Hooke's Law)

Elastic PE = ½Fx = ½kx²

σ = F/A (stress, Pa)

ε = x/L (strain, no unit)

E = σ/ε (Young modulus, Pa)

Elastic limit: Giới hạn đàn hồi — vượt qua → biến dạng dẻo vĩnh viễn

AS · Topic 7

Waves

Wave Equations & Properties

v = fλ

f = 1/T

I = P/A (intensity)

Transverse: Rung ⊥ truyền. Polarisable. VD: EM waves, sóng dây

Longitudinal: Rung // truyền. Không polarise. VD: âm thanh

Doppler effect: f₀ = fₛ × v / (v ± vₛ)

Young's double slit: λ = ax / D (a = slit separation, D = distance)

Diffraction grating: d sinθ = nλ

Stationary wave: Superposition of 2 waves in opposite directions. Nodes + antinodes. f₁ = v/2L

AS · Topic 8

Current Electricity

Circuit Formulas

I = Q/t = nAvq

V = W/Q

R = V/I = ρL/A

P = IV = I²R = V²/R

KCL: ∑I_in = ∑I_out | KVL: ∑ε = ∑IR

Series: R = R₁ + R₂

Parallel: 1/R = 1/R₁ + 1/R₂

Potential divider: V₂ = V_in × R₂/(R₁+R₂)

Internal resistance: ε = I(R + r) · V = ε − Ir

Worked Example

AS · Topic 8

VD4 · Internal resistance

Pin: ε = 1.5 V, r = 0.5 Ω, R = 2.5 Ω. Tìm I và terminal voltage V.

✓ Solution

ε = I(R + r)
1.5 = I(2.5 + 0.5) = 3I
I = 0.5 A

Terminal voltage:
V = ε − Ir = 1.5 − (0.5)(0.5) = 1.5 − 0.25 = 1.25 V

AS · Topic 9

Particle Physics

Fundamental Particles

Particle	Charge	Baryon #	Lepton #
Proton (uud)	+1	+1	0
Neutron (udd)	0	+1	0
Electron	−1	0	+1
Neutrino (νₑ)	0	0	+1
Positron (e⁺)	+1	0	−1

Quarks

Quark	Charge	Baryon #
Up (u)	+2/3	1/3
Down (d)	−1/3	1/3
Strange (s)	−1/3	1/3

Hadrons, Mesons & Leptons

Baryon: 3 quarks. Proton = uud · Neutron = udd

Meson: quark + antiquark. Pion π⁺ = uđ̄

Lepton: electron, neutrino. Không chịu strong nuclear force

Radioactive Decay Equations

α decay: ᴬ_Z X → ᴬ⁻⁴_(Z−2) Y + ⁴_₂ He

β⁻ decay: n → p + e⁻ + ν̄ₑ

β⁺ decay: p → n + e⁺ + νₑ

Baryon number, lepton number, charge conserved in all decays

A2 · Topic 10

Circular Motion

Circular Motion Equations

ω = 2πf = 2π/T

v = rω

a = v²/r = rω² (centripetal)

F = mv²/r = mrω²

Centripetal force sources: Gravity (satellite) · Tension (string) · Friction (car cornering) · Normal (loop)

Worked Example

A2 · Topic 10

VD5 · Satellite orbit

Vệ tinh 500 kg, r = 6.8 × 10⁶ m, v = 7700 m/s. Tìm lực hướng tâm.

✓ Solution

F = mv²/r
  = (500)(7700²) / (6.8 × 10⁶)
  = 500 × 59 290 000 / 6 800 000
  = 4360 N

A2 · Topic 11

Gravitational Fields

Gravitational Field Equations

g = F/m (field strength)

F = GMm/r² (force)

g = GM/r²

φ = −GM/r (potential)

Eₚ = −GMm/r

Orbital speed: v = √(GM/r)

Kepler's 3rd law: T² = (4π²/GM) × r³

Geostationary orbit: T = 24h · Equatorial · r ≈ 42 200 km · Same angular velocity as Earth

A2 · Topic 12

Temperature & Ideal Gases

Thermal & Kinetic Theory

T(K) = T(°C) + 273

pV = nRT = NkT

pV = ⅓Nm<c²> (kinetic model)

½m<c²> = 3/2 kT (mean KE per molecule)

n = moles · N = molecules · R = 8.31 J mol⁻¹ K⁻¹ · k = 1.38×10⁻²³ J K⁻¹

A2 · Topic 13

Oscillations (SHM)

Simple Harmonic Motion

a = −ω²x (defining equation of SHM)

x = x₀ sin ωt

v = ±ω√(x₀²−x²)

v_max = ωx₀

Spring: T = 2π√(m/k)

Pendulum: T = 2π√(l/g)

Damping & Resonance

Light damping: Amplitude giảm dần, frequency giữ nguyên
Critical damping: Trở về cân bằng nhanh nhất, không dao động
Heavy (overdamping): Chậm trở về, không dao động
Resonance: f_applied = f_natural → A max. Damping giảm amplitude và mở rộng peak

A2 · Topic 14

Electric Fields

Electric Field Equations

E = F/q (field strength)

Uniform field: E = V/d

Coulomb: F = Qq/(4πε₀r²)

E = Q/(4πε₀r²)

V = Q/(4πε₀r) (potential due to point charge)

Analogy with gravity: E ~ g · V_elec ~ φ_grav (but +/− charges, +/+ gravity)

A2 · Topic 15

Capacitance

Capacitance Equations

C = Q/V

C = ε₀εᵣA/d (parallel plate)

W = ½QV = ½CV²

Parallel: C = C₁ + C₂

Series: 1/C = 1/C₁ + 1/C₂

Discharge: Q = Q₀ e^(−t/RC) · V = V₀ e^(−t/RC) · τ = RC (time constant)

Worked Example

A2 · Topic 15

VD6 · Capacitor discharge

C = 100 μF, V₀ = 12 V, R = 50 kΩ. Tìm voltage V sau 5 s.

✓ Solution

Time constant:
τ = RC = (50×10³)(100×10⁻⁶) = 5 s

V = V₀ e^(−t/τ)
  = 12 × e^(−5/5)
  = 12 × e⁻¹
  = 12 × 0.368
  = 4.41 V

A2 · Topic 16

Magnetic Fields

Magnetic Force & Induction

F = BIl sinθ (on wire)

F = Bqv sinθ (on charge)

r = mv/(Bq) (circular motion)

Fleming's LHR: thuNb = Force · First = B-field · seCond = conventional I

Faraday's law: ε = −Δ(NΦ)/Δt (EMF = rate of change of flux linkage)

Lenz's law: Induced EMF opposes the change causing it

Φ = BA cosθ

A2 · Topic 17

Quantum Physics

Photons, Photoelectric Effect & de Broglie

E = hf = hc/λ (photon energy)

Photoelectric: hf = φ + KE_max (φ = work function = hf₀)

f₀ = φ/h (threshold frequency)

λ = h/p = h/(mv) (de Broglie)

Key points: Intensity↑ → more electrons, KE unchanged · Frequency↑ → KE↑

Energy levels: hf = E₂ − E₁ (photon emitted in transition)

A2 · Topic 18

Nuclear Physics

Mass–Energy & Radioactive Decay

E = mc² (mass–energy equivalence)

Mass defect: Δm = Zmₚ + Nmₙ − m_nucleus

Binding energy = Δmc² · Max BE/A at Fe-56 (most stable)

N = N₀ e^(−λt)

A = A₀ e^(−λt)

Decay constant: λ = ln2 / t½

Worked Example

A2 · Topic 18

VD7 · Radioactive decay

t½ = 8 ngày, A₀ = 6400 Bq. Tìm activity A sau 24 ngày.

✓ Solution

Số half-lives = 24 / 8 = 3 half-lives

A₀ = 6400 Bq
After 1 half-life: 3200
After 2 half-lives: 1600
After 3 half-lives: 800 Bq

Verify with formula:
λ = ln2/8 = 0.0866 day⁻¹
A = 6400 × e^(−0.0866×24) = 6400 × 0.125 = 800 Bq ✓

A2 · Topic 19

Medical Physics

Medical Imaging Modalities

X-ray: High-energy photons · I = I₀ e^(−μx) · CT = nhiều X-ray góc khác → 3D reconstruction

Ultrasound: >20 kHz · Phản xạ tại boundaries (acoustic impedance change) · An toàn · d = vt/2

PET scan: β⁺ → annihilation → 2γ photons at 180° · Functional imaging (metabolic activity)

Phụ lục · AS Level

Formula Sheet — AS

Formula	Value / Form	Topic
v = u+at · s = ut+½at²	v² = u²+2as · s = ½(u+v)t	Kinematics
F = ma · p = mv	Δp = FΔt · W = mg	Dynamics
Moment = F×d	Torque = F×d (couple)	Turning
ρ = m/V · p = F/A	Δp = ρgΔh	Density/Pressure
W = Fs cosθ · KE = ½mv²	GPE = mgh · P = W/t = Fv	Energy/Power
F = kx · Elastic PE = ½kx²	σ = F/A · ε = x/L · E = σ/ε	Solids
v = fλ · I = P/A	λ = ax/D · d sinθ = nλ	Waves
I = Q/t = nAvq	R = V/I = ρL/A · P = IV	Electricity
ε = I(R+r)	V₂ = V_in × R₂/(R₁+R₂)	Circuits

Phụ lục · A2 Level

Formula Sheet — A2

Formula	Value / Form	Topic
ω = 2πf · v = rω	a = v²/r · F = mv²/r	Circular motion
F = GMm/r² · g = GM/r²	φ = −GM/r · T² = (4π²/GM)r³	Gravity
pV = nRT = NkT	½m<c²> = 3/2 kT	Gases
a = −ω²x · v_max = ωx₀	T = 2π√(m/k) · T = 2π√(l/g)	SHM
F = Qq/4πε₀r² · E = V/d	V = Q/4πε₀r	E-field
C = Q/V · W = ½CV²	Q = Q₀e^(−t/RC) · τ = RC	Capacitance
F = BIl · F = Bqv	r = mv/Bq · ε = −Δ(NΦ)/Δt	B-field
E = hf · hf = φ + KE_max	λ = h/p	Quantum
E = mc² · BE = Δmc²	N = N₀e^(−λt) · λ = ln2/t½	Nuclear

kₛ

Phụ lục

Key Physical Constants

Constant	Value	Description
c	3.00 × 10⁸ m s⁻¹	Speed of light in vacuo
h	6.63 × 10⁻³⁴ J s	Planck constant
e	1.60 × 10⁻¹⁹ C	Elementary charge
mₑ	9.11 × 10⁻³¹ kg	Rest mass of electron
mₚ	1.67 × 10⁻²⁷ kg	Rest mass of proton
G	6.67 × 10⁻¹¹ N m² kg⁻²	Gravitational constant
Nₐ	6.02 × 10²³ mol⁻¹	Avogadro constant
k	1.38 × 10⁻²³ J K⁻¹	Boltzmann constant
R	8.31 J mol⁻¹ K⁻¹	Molar gas constant
ε₀	8.85 × 10⁻¹² F m⁻¹	Permittivity of free space
g	9.81 m s⁻²	Gravitational field strength (Earth surface)
1 eV	1.60 × 10⁻¹⁹ J	Electronvolt in joules
1 u	1.66 × 10⁻²⁷ kg	Unified atomic mass unit

TIMES EDU PRESS

A Level Physics 9702 · Cambridge International · Song ngữ Việt–Anh