📚 AS Physics: End-of-Term Revision Guide | AS 物理：期末复习提纲
This comprehensive revision checklist covers the essential topics, key formulas, and common problem types for AS-level Physics. Use it to structure your final review, identify weak areas, and ensure you can apply each concept confidently in an exam setting.
这份全面的复习提纲涵盖了 AS 物理的核心主题、关键公式和常见题型。你可以用它来规划期末复习、找出薄弱环节，并确保能够在考试中自信地运用每个概念。
1. Kinematics | 运动学
Scalars have magnitude only (e.g., speed, distance, mass), while vectors have both magnitude and direction (e.g., velocity, displacement, acceleration).
标量只有大小（如速率、路程、质量），矢量既有大小又有方向（如速度、位移、加速度）。
The SUVAT equations link displacement s, initial velocity u, final velocity v, constant acceleration a, and time t.
SUVAT 方程将位移 s、初速度 u、末速度 v、恒定加速度 a 和时间 t 联系起来。
v = u + at
s = (u + v)t / 2
s = ut + ½at²
v² = u² + 2as
For vertical motion under gravity, replace a with g (9.81 m s⁻²) and remember to define the positive direction consistently.
对于重力作用下的竖直运动，将 a 替换为 g (9.81 m s⁻²)，并始终明确定义正方向。
The gradient of a displacement–time graph gives velocity; the gradient of a velocity–time graph gives acceleration, and the area under a velocity–time graph gives displacement.
位移–时间图像的斜率表示速度；速度–时间图像的斜率表示加速度，其下的面积表示位移。
2. Dynamics and Newton’s Laws | 动力学与牛顿定律
Newton’s First Law: an object remains at rest or in uniform motion unless acted upon by a resultant force.
牛顿第一定律：物体将保持静止或匀速直线运动状态，除非受到合外力的作用。
Newton’s Second Law: F = ma, where F is the resultant force in newtons, m is mass in kg, and a is acceleration in m s⁻².
牛顿第二定律：F = ma，其中 F 为合外力（单位 N），m 为质量（kg），a 为加速度（m s⁻²）。
Newton’s Third Law: if body A exerts a force on body B, then body B exerts an equal and opposite force on body A; these forces act on different bodies.
牛顿第三定律：若物体 A 对物体 B 施加一个力，则 B 会同时对 A 施加一个大小相等、方向相反的力；这两个力作用在不同物体上。
Momentum p = mv; impulse = force × time = change in momentum = Δp. In collisions, total momentum is conserved if no external resultant force acts.
动量 p = mv；冲量 = 力 × 时间 = 动量的变化 = Δp。在没有合外力作用时，碰撞过程中总动量守恒。
Draw free-body diagrams showing all forces: weight, normal reaction, tension, friction, and applied forces. Resolve components along perpendicular axes.
绘制受力分析图，标出所有力：重力、法向反作用力、拉力、摩擦力和施加的外力。将力沿垂直坐标轴分解。
3. Work, Energy and Power | 功、能与功率
Work done W = F d cos θ, where θ is the angle between the force and the direction of motion. Work is measured in joules (J).
做功 W = F d cos θ，其中 θ 为力与运动方向的夹角。功的单位为焦耳 (J)。
Kinetic energy E_k = ½mv²; gravitational potential energy E_p = mgh (near the Earth’s surface). Energy is a scalar and is always conserved in a closed system.
动能 E_k = ½mv²；重力势能 E_p = mgh （在地表附近）。能量是标量，在封闭系统中总能量守恒。
Power P = work done / time taken = ΔW / Δt; for an object moving at constant speed against a constant force, P = Fv.
功率 P = 做功 / 所用时间 = ΔW / Δt；对于克服恒定力匀速运动的物体，P = Fv。
Efficiency = useful energy output / total energy input × 100%.
效率 = 有用能量输出 / 总能量输入 × 100%。
4. Materials: Hooke’s Law and Young Modulus | 材料：胡克定律与杨氏模量
Hooke’s law states that extension x is proportional to the applied force F, up to the limit of proportionality: F = kx, where k is the spring constant.
胡克定律指出，在比例极限内，伸长量 x 与所施加的力 F 成正比：F = kx，k 为劲度系数。
The elastic limit is the point beyond which the material is permanently deformed. Stress σ = F/A; strain ε = x/L.
弹性极限是材料发生永久形变的临界点。应力 σ = F/A；应变 ε = x/L。
Young modulus E = σ / ε = (F L) / (A x). It describes the stiffness of a material and is measured in pascals (Pa).
杨氏模量 E = σ / ε = (F L) / (A x)。它反映材料的刚度，单位为帕斯卡 (Pa)。
The area under a force–extension graph gives the work done (elastic potential energy). For a spring obeying Hooke’s law, E_elastic = ½Fx = ½kx².
力–伸长量图像下的面积代表所做的功（弹性势能）。对于遵守胡克定律的弹簧，弹性势能 E_弹 = ½Fx = ½kx²。
5. Waves | 波
A wave transfers energy without transferring matter. The wave speed v = fλ, where f is frequency and λ is wavelength.
波传递能量而不传递物质。波速 v = fλ，f 为频率，λ 为波长。
Transverse waves have particle oscillations perpendicular to the direction of energy transfer (e.g., light, water ripples). Longitudinal waves have oscillations parallel to the direction of energy transfer (e.g., sound).
横波的质点振动方向与能量传递方向垂直（如光、水波纹）。纵波的质点振动方向与能量传递方向平行（如声波）。
The electromagnetic spectrum, in order of increasing frequency: radio, microwave, infrared, visible, ultraviolet, X-ray, gamma. All travel at c = 3.00 × 10⁸ m s⁻¹ in a vacuum.
电磁波谱按频率递增顺序：无线电波、微波、红外线、可见光、紫外线、X 射线、γ 射线。所有电磁波在真空中均以 c = 3.00 × 10⁸ m s⁻¹ 传播。
Refraction: when waves enter a medium with a different refractive index, their speed and wavelength change, but frequency stays constant. n₁ sin θ₁ = n₂ sin θ₂ (Snell’s law).
折射：波进入折射率不同的介质时，波速和波长改变，频率保持不变。n₁ sin θ₁ = n₂ sin θ₂（斯涅耳定律）。
Total internal reflection occurs when light travels from a higher to a lower refractive index and the angle of incidence exceeds the critical angle C, where sin C = n₂ / n₁ (n₂ < n₁).
当光从光密介质射向光疏介质，且入射角大于临界角 C 时，发生全内反射。sin C = n₂ / n₁ (n₂ < n₁)。
6. Superposition and Interference | 叠加与干涉
The principle of superposition: when two waves meet, the resultant displacement is the algebraic sum of the individual displacements.
叠加原理：两列波相遇时，合位移等于各分位移的代数和。
Constructive interference occurs when waves arrive in phase (path difference = nλ); destructive interference occurs when waves are out of phase (path difference = (n + ½)λ).
当波的相位相同（波程差 = nλ）时，发生相长干涉；当波反相（波程差 = (n + ½)λ）时，发生相消干涉。
Young’s double-slit fringe spacing: Δx = λD / d, where D is slit-to-screen distance and d is slit separation.
杨氏双缝干涉条纹间距：Δx = λD / d，其中 D 为缝屏间距，d 为双缝间距。
For a diffraction grating: d sin θ = nλ, where d is the slit spacing (1 / lines per metre), n is the order. This equation can be used to measure wavelength precisely.
衍射光栅方程：d sin θ = nλ，d 为光栅常数（1/每米刻线数），n 为级数。该式可用于精确测量波长。
Stationary waves form when two identical progressive waves travel in opposite directions. Nodes have zero displacement; antinodes have maximum amplitude. The distance between adjacent nodes is λ/2.
当两列相同的行波沿相反方向传播时，形成驻波。波节处位移为零；波腹处振幅最大。相邻波节间距为 λ/2。
7. Electric Fields and Current | 电场与电流
Electric current I = ΔQ / Δt, measured in amperes (A). Conventional current flows from positive to negative.
电流 I = ΔQ / Δt，单位为安培 (A)。约定电流方向由正到负。
Potential difference V = W / Q, where W is work done. The volt is one joule per coulomb.
电势差（电压）V = W / Q，W 为做功。1 伏特 = 1 焦耳/库仑。
Resistance R = V / I; ohm’s law states that V ∝ I for a conductor at constant temperature. Resistivity ρ = RA / L, giving R = ρL / A.
电阻 R = V / I；欧姆定律指出，在温度不变时 V ∝ I。电阻率 ρ = RA / L，即 R = ρL / A。
The I–V characteristic of a filament lamp is curved because its resistance increases with temperature. A diode conducts only when forward-biased.
白炽灯的 I–V 特性曲线弯曲，因其电阻随温度升高而增大。二极管仅在正向偏置时导通。
8. D.C. Circuits and Kirchhoff’s Laws | 直流电路与基尔霍夫定律
Kirchhoff’s Current Law (KCL): sum of currents entering a junction = sum of currents leaving. Kirchhoff’s Voltage Law (KVL): sum of e.m.f.s = sum of p.d.s around any closed loop.
基尔霍夫电流定律 (KCL)：流入节点的电流之和等于流出节点的电流之和。基尔霍夫电压定律 (KVL)：任一闭合回路中，电动势总和等于各元件上的电压降总和。
Resistors in series: R_total = R₁ + R₂ + …; in parallel: 1/R_total = 1/R₁ + 1/R₂ + …
串联电阻：R_总 = R₁ + R₂ + …；并联电阻：1/R_总 = 1/R₁ + 1/R₂ + …
A potential divider splits voltage according to resistance ratio: V_out = V_in × (R₂ / (R₁ + R₂)).
分压器按电阻比例分配电压：V_out = V_in × (R₂ / (R₁ + R₂))。
The e.m.f. ε of a source is the energy supplied per coulomb. Its terminal p.d. is V = ε – Ir, where r is the internal resistance.
电源的电动势 ε 是每库仑提供的能量。端电压 V = ε – Ir，r 为内阻。
Power dissipated in a resistor: P = IV = I²R = V²/R.
电阻消耗的功率：P = IV = I²R = V²/R。
9. Particle Physics and Radioactivity | 粒子物理与放射性
The nucleus contains protons and neutrons (nucleons). Nuclide notation: ᴬZ X, where Z is the atomic (proton) number, A is the mass (nucleon) number.
原子核包含质子和中子（统称核子）。核素符号：ᴬZ X，Z 为原子序数（质子数），A 为质量数（核子数）。
Isotopes are atoms of the same element with the same Z but different A. The strong nuclear force binds nucleons together, overcoming electrostatic repulsion between protons.
同位素是同一元素的不同原子，质子数 Z 相同但质量数 A 不同。强核力将核子结合在一起，克服质子间的静电斥力。
Alpha decay: nucleus emits an α-particle (⁴₂He), decreasing A by 4 and Z by 2. Beta-minus decay: a neutron converts to a proton, emitting an electron (β⁻) and an antineutrino, Z increases by 1. Gamma decay: emission of high-energy photon, A and Z unchanged.
α 衰变：原子核放出 α 粒子（⁴₂He），A 减 4，Z 减 2。β⁻ 衰变：中子转变为质子，放出一个电子 (β⁻) 和一个反中微子，Z 增加 1。γ 衰变：放出高能光子，A 和 Z 不变。
Activity A is the number of decays per second (becquerels, Bq). Half-life T½ is the time for activity or number of nuclei to halve. Exponential decay: N = N₀ e^(−λt), A = A₀ e^(−λt), where λ = ln 2 / T½.
活度 A 是每秒衰变次数（单位 Bq）。半衰期 T½ 是活度或原子核数减半所需的时间。指数衰减规律：N = N₀ e^(−λt)，A = A₀ e^(−λt)，其中 λ = ln 2 / T½。
Nuclear reactions must balance mass numbers and atomic numbers on both sides. Energy released can be calculated from mass defect via E = Δm c².
核反应方程需满足质量数和电荷数守恒。释放的能量可通过质量亏损用 E = Δm c² 计算。
10. Quantum Physics: Photoelectric Effect | 量子物理：光电效应
Photoelectric effect: electrons are emitted from a metal surface when it is illuminated by electromagnetic radiation of frequency above a threshold frequency f₀.
光电效应：当金属表面被频率高于阈值频率 f₀ 的电磁辐射照射时，会发射出电子。
Photon energy E = hf = hc/λ, where h is Planck’s constant. A photon interacts with a single electron; emission is instantaneous if hf > φ.
光子能量 E = hf = hc/λ，h 为普朗克常量。光子与单个电子相互作用；若 hf > φ，电子立即发射。
Work function φ is the minimum energy needed to release an electron from the metal. Einstein’s photoelectric equation: E_k max = hf – φ.
功函数 φ 是从金属中释放一个电子所需的最小能量。爱因斯坦光电效应方程：E_k max = hf – φ。
Stopping potential V_s relates to maximum kinetic energy: e V_s = E_k max. The graph of V_s against f yields a gradient of h/e and intercept −φ/e.
遏止电压 V_s 与最大动能的关系：e V_s = E_k max。V_s – f 图线的斜率为 h/e，截距为 −φ/e。
The wave theory could not explain the existence of a threshold frequency or the instantaneous emission; the photon model successfully accounts for these observations.
波动理论无法解释阈值频率的存在和瞬时发射现象；光子模型则成功地解释了这些观察结果。
Published by TutorHao | Physics Revision Series | aleveler.com
更多咨询请联系16621398022（同微信）
屏轩国际教育cambridge primary/secondary checkpoint, cat4, ukiset,ukcat,igcse,alevel,PAT,STEP,MAT, ibdp,ap,ssat,sat,sat2课程辅导，国外大学本科硕士研究生博士课程论文辅导Cancel reply