📚 Year 11 CIE Physics: Core Concepts Overview | Year 11 CIE 物理：核心知识点梳理
This comprehensive overview covers the essential topics for Year 11 CIE IGCSE Physics. We systematically go through motion, forces, energy, thermal physics, waves, electricity, magnetism, atomic physics and key practical skills. Each concept is presented in a concise bilingual format to reinforce understanding and boost exam readiness.
这篇文章全面梳理了 Year 11 CIE IGCSE 物理的核心知识点，涵盖运动学、力学、能量、热物理、波、电学、磁学、原子物理和重要实验技能。每个要点都以中英双语简明呈现，帮助巩固理解并提升应试能力。
1. Kinematics: Describing Motion | 运动学：描述运动
Distance is the total length of a path travelled, while displacement is the straight-line distance in a given direction. Speed is the rate of change of distance, and velocity is the rate of change of displacement.
距离是物体路径的总长度，位移是带有方向的直线距离。速率是距离的变化率，速度是位移的变化率。
initial velocity, v is final velocity, a is acceleration, t is time and s is displacement.
匀加速运动的三个方程为：v = u + at，s = ut + ½at²，v² = u² + 2as。其中 u 为初速度，v 为末速度，a 为加速度，t 为时间，s 为位移。
Acceleration of free fall near the Earth's surface is approximately 9.8 m/s². In the absence of air resistance, all objects fall at the same rate regardless of mass.
地表附近的自由落体加速度约为 9.8 m/s²。忽略空气阻力时，所有物体无论质量大小都会以相同速率下落。
On a speed–time graph, the gradient gives acceleration and the area under the graph represents distance travelled. A horizontal line indicates constant speed.
在速率-时间图中，斜率表示加速度，图线下的面积代表走过的距离。水平线表示恒定速率。
2. Dynamics: Forces and Newton's Laws | 动力学：力与牛顿定律
A force can change an object's speed, direction or shape. Forces are vector quantities; the resultant force is found by vector addition.
力可以改变物体的速率、方向或形状。力是矢量，合力的计算基于矢量加法。
Newton' ains at rest or in uniform motion unless acted upon by an external resultant force. Newton' cond law states that resultant force F = ma, where m is mass and a is acceleration. Newton' t if body A exerts a force on body B, body B exerts an equal and opposite force on body A.
牛顿第一定律指出，若不受外力作用，物体将保持静止或匀速直线运动。牛顿第二定律表述为合力 F = ma，m 为质量，a 为加速度。牛顿第三定律指出作用力与反作用力大小相等、方向相反，作用在不同物体上。
ce on a mass: W = mg. Mass is constant; weight varies with gravitational field strength g.
重量是作用在质量上的引力：W = mg。质量不变，重量随引力场强度 g 变化。
Friction opposes motion and can be static or dynamic. Terminal velocity occurs when the resultant force on a falling object becomes zero, so acceleration ceases and speed becomes constant.
摩擦力阻碍运动，分为静摩擦和动摩擦。当坠落的物体合力为零时达到终端速度，加速度为零，速度保持恒定。
3. Energy, Work and Power | 能量、功和功率
Energy is the capacity to do work and is measured in joules (J). The principle of conservation of energy states that energy cannot be created or destroyed, only transferred or transformed.
能量是做功的本领，单位为焦耳（J）。能量守恒定律指出能量不能被创造或消灭，只能被转移或转化。
tional potential energy Eₚ = mgh. These two forms interconvert in many mechanical systems.
动能 Eₖ = ½mv²。重力势能 Eₚ = mgh。在许多机械系统中，这两种形式的能量相互转化。
doing work: P = W/t or P = E/t. An alternative expression for mechanical power is P = Fv.
功 W = Fd，其中力 F 沿位移 d 方向作用。功率是做功的速率：P = W/t 或 P = E/t。机械功率的另一种表达为 P = Fv。
Efficiency = (useful energy output / total energy input) × 100% rocess, some energy is dissipated as thermal energy, so efficiency is always less than 100%.
效率 =（有用能量输出 / 总能量输入）× 100%。在任何实际过程中，部分能量会以热能形式耗散，因此效率始终小于 100%。
Energy resources are classified as renewable (solar, wind, tidal, hydroelectric, geothermal) and non-renewable (fossil fuels, nuclear). The choice of resource involves considerations of availability, environmental impact, cost and energy density.
能源分为可再生能源（太阳能、风能、潮汐能、水能、地热能）和不可再生能源（化石燃料、核能）。选择能源时需考虑可用性、环境影响、成本和能量密度。
4. Thermal Physics: Heat and Temperature | 热物理：热量与温度
Temperature is a measure of the average kinetic energy of particles in a substance. Heat is the transfer of thermal energy from a region of higher temperature to a region of lower temperature.
温度是物质内粒子平均动能的量度。热量是从高温区域向低温区域转移的热能。
The three modes of heat transfer are conduction, convection and radiation. Conduction occurs mainly in solids via lattice vibrations and free electrons; convection occurs in fluids due to density changes; radiation is transfer by electromagnetic waves and does not require a medium.
热传递的三种方式是传导、对流和辐射。传导主要在固体中通过晶格振动和自由电子进行；对流在流体中因密度变化而发生；辐射通过电磁波传递，不需要介质。
ergy needed to change the state of 1 kg of a substance without temperature change: Q = mL.
比热容 c 是使 1 kg 物质温度升高 1 °C 所需的能量：Q = mcΔθ。比潜热 L 是使 1 kg 物质在不改变温度的情况下发生物态变化所需的能量：Q = mL。
During melting and boiling, temperature remains constant even though energy is being supplied; this energy goes into breaking intermolecular bonds rather than increasing kinetic energy.
熔化和沸腾过程中，尽管持续供能，温度仍保持不变；这些能量用于打破分子间键合，而非增加动能。
The pressure of a fixed mass of gas at constant volume increases with temperature (p ∝ T, where T is in kelvin). The Kelvin scale starts at absolute zero (0 K = –273 °C) and does not use the degree sign.
定容条件下固定质量气体的压强随温度升高（p ∝ T，T 以开尔文为单位）。开尔文温标以绝对零度（0 K = –273 °C）为起点，不使用度符号。
5. Wave Properties | 波的性质
A wave transfers energy from one point to another without net movement of the medium. Transverse waves have 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).
波将能量从一点传递到另一点，没有介质的净移动。横波的振动方向与能量传递方向垂直（如光、水波）。纵波的振动方向与能量传递方向平行（如声音）。
s per second, in hertz), amplitude (maximum displacement from rest) and wave speed v = fλ.
波的关键术语：波长 λ（两个相邻波峰或稠密间的距离），频率 f（每秒的波数，单位为赫兹），振幅（离开平衡位置的最大位移）和波速 v = fλ。
Reflection occurs when a wave strikes a boundary and bounces back; the angle of incidence equals the angle of reflection. Refraction is the change in direction of a wave as it enters a different medium, caused by a change in speed.
反射发生在波遇到界面并反弹时，入射角等于反射角。折射是波进入不同介质时因速度改变而导致的方向变化。
ngth. The electromagnetic spectrum, in order of increasing frequency, includes radio, microwave, infrared, visible, ultraviolet, X-ray and gamma rays, all travelling at 3.0 × 10⁸ m/s in a vacuum.
衍射是波绕过障碍物或穿过狭缝时的扩散现象，当狭缝宽度与波长相近时衍射最明显。电磁波谱按频率递增顺序包括无线电波、微波、红外线、可见光、紫外线、X 射线和伽马射线，所有电磁波在真空中的速度均为 3.0 × 10⁸ m/s。
6. Sound and Light | 声与光
Sound is a longitudinal wave that requires a medium to travel. It travels fastest in solids, slower in liquids and slowest in gases. The range of audible frequencies for humans is approximately 20 Hz to 20 000 Hz.
声音是纵波，需要介质传播。声音在固体中最快，液体中较慢，气体中最慢。人耳可听见的频率范围约为 20 Hz 至 20 000 Hz。
Ultrasound has frequencies above 20 kHz and is used in sonar, medical imaging and cleaning. Echoes are reflections of sound; the time delay between emission and reception can be used to measure distances.
超声波频率高于 20 kHz，用于声纳、医学成像和清洗。回声是声音的反射，利用发射与接收之间的时间间隔可以测量距离。
inverted and the same size as the object. The law of reflection holds: angle i = angle r.
光是横电磁波。平面镜反射时，形成的像是虚像、正立、左右颠倒且与物体等大。反射定律成立：入射角 i 等于反射角 r。
Refraction of light is governed by Snell' ction can occur if the angle of incidence exceeds the critical angle c, where sin c = 1/n.
光的折射遵循斯涅尔定律：n = sin i / sin r，n 为折射率。当光从光密介质射向光疏介质，且入射角大于临界角 c（sin c = 1/n）时，会发生全反射。
tual, magnified image when the object is inside the focal length. The thin lens formula is 1/f = 1/u + 1/v.
透镜可以成实像或虚像。凸透镜（会聚透镜）当物体在焦点外时可成倒立实像，当物体在焦距内时成正立放大的虚像。薄透镜公式为 1/f = 1/u + 1/v。
7. Electricity: Circuits and Components | 电学：电路与元件
(A). In a closed circuit, conventional current flows from the positive to the negative terminal.
电流是电荷流动的速率：I = Q/t，单位是安培（A）。在闭合电路中，惯例电流方向从正极流向负极。
W/Q is the energy transferred per unit charge across a component. Resistance R = V/I; ohm's law states that V ∝ I for an ohmic conductor at constant temperature.
电动势（e.m.f.）是电源每单位电荷转换的能量。电势差（p.d.）V = W/Q 是通过元件每单位电荷转换的能量。电阻 R = V/I；欧姆定律指出，在恒温下欧姆导体的 V ∝ I。
In a series circuit: current is the same everywhere; total resistance Rₜ = R₁ + R₂ + … l current is the sum of branch currents; total resistance is given by 1/Rₜ = 1/R₁ + 1/R₂ + ….
串联电路中：各处电流相同；总电阻 Rₜ = R₁ + R₂ + …；各元件电压之和等于电源电压。并联电路中：各支路电压相等；总电流等于各支路电流之和；总电阻的倒数等于各支路电阻倒数之和：1/Rₜ = 1/R₁ + 1/R₂ + …。
ionships are essential for calculating energy consumption and selecting appropriate fuses.
电功率 P = IV = I²R = V²/R。电能 E = IVt。这些关系式对于计算能耗和选择合适保险丝至关重要。
Key circuit components include fixed resistors, variable resistors (rheostats), diodes (allow current in one direction only), light-dependent resistors (LDRs, resistance decreases with light intensity) and thermistors (resistance decreases as temperature increases).
关键电路元件包括固定电阻器、可变电阻器（变阻器）、二极管（只允许单向导电）、光敏电阻（电阻随光照强度增加而减小）和热敏电阻（电阻随温度升高而减小）。
8. Magnetism and Electromagnetism | 磁学与电磁学
A magnet has a north and a south pole. Like poles repel, unlike poles attract. Magnetic field lines are directed from north to south outside a magnet and indicate the direction of the force on a north pole.
磁铁具有北极和南极。同名磁极相斥，异名磁极相吸。磁感线在磁铁外部从北极指向南极，表示北极受力的方向。
An electric current produces a magnetic field. The direction of the field around a straight wire is given by the right-hand grip rule. A solenoid (coil) creates a strong uniform field inside; its polarity can be determined by the grip rule and its strength increased by adding a soft iron core, increasing the current or increasing the number of turns.
电流产生磁场。直导线周围的磁场方向由右手定则确定。螺线管（线圈）内部产生强而匀强的磁场；极性可由右手螺旋定则判定，其强度可以通过插入软铁芯、增大电流或增加匝数来增强。
t-carrying conductor is placed in an external magnetic field, resulting in a force. Fleming's left-hand rule gives the relative directions of field, current and force: thumb – force, first finger – field, second finger – re B is magnetic flux density, I is current and L is the length of conductor in the field.
电动机效应：当载流导体置于外磁场中时，会受到力的作用。弗莱明左手定则表示磁场、电流和力的方向：拇指–力，食指–磁场，中指–电流。力的大小 F = BIL，其中 B 为磁通量密度，I 为电流，L 为导体在磁场中的长度。
A simple d.c. motor uses a coil in a magnetic field and a split-ring commutator to reverse current every half turn, ensuring continuous rotation. Electromagnetic induction is the generation of an e.m.f. across a conductor when it experiences a changing magnetic field.
简单直流电动机利用磁场中的线圈和换向器（开口环）每半圈反转电流方向，从而持续旋转。电磁感应是当导体处于变化的磁场中时，在导体两端产生的电动势。
Faraday' nduce an e.m.f. in a secondary coil. For an ideal transformer: Vₚ/Vₛ = Nₚ/Nₛ, and power input equals power output (VₚIₚ = VₛIₛ).
法拉第定律：感应电动势的大小与磁链变化率成正比。变压器利用初级线圈中的交流电在次级线圈中感应出电动势。理想变压器满足：Vₚ/Vₛ = Nₚ/Nₛ，且输入功率等于输出功率（VₚIₚ = VₛIₛ）。
9. Atomic Structure and Radioactivity | 原子结构与放射性
The nuclear atom consists of a small central nucleus containing protons (positive) and neutrons (neutral), surrounded by electrons (negative) in energy levels. Atomic number Z is the number of protons; mass number A is the total number of nucleons (protons + neutrons).
核式原子由一个微小的中央原子核和核外分层排布的电子组成。原子核内含质子（带正电）和中子（不带电）。原子序数 Z 是质子数；质量数 A 是核子总数（质子 + 中子）。
Isotopes are atoms of the same element with the same number of protons but different numbers of neutrons. Radioactive decay is spontaneous and random; it results in the emission of alpha particles (α, helium nuclei ⁴₂He), beta particles (β⁻, high-speed electrons) or gamma rays (γ, electromagnetic waves).
同位素是质子数相同但中子数不同的同种元素的原子。放射性衰变是自发且随机的，会放射出 α 粒子（氦核 ⁴₂He）、β⁻ 粒子（高速电子）或 γ 射线（电磁波）。
Alpha particles have low penetration (stopped by paper) but high ionising power. Beta particles penetrate a few mm of aluminium; gamma rays are highly penetrating (reduced by thick lead or concrete) with low ionising power.
α 粒子穿透力弱（可被纸阻挡），但电离能力强。β 粒子可穿透几毫米铝板；γ 射线穿透力极强（需厚铅或混凝土减弱），电离能力弱。
Half-life is the average time taken for half the nuclei in a sample to decay. It is constant for a given isotope. Background radiation comes from sources such as cosmic rays, rocks, radon gas and medical applications.
半衰期是指样品中一半原子核发生衰变平均所需的时间，对特定同位素是常数。背景辐射源自宇宙射线、岩石、氡气及医疗用途等。
Nuclear equations balance total nucleon number and proton number. An α decay reduces Z by 2 and A by 4. A β⁻ decay increases Z by 1 with A unchanged, as a neutron changes to a proton and an electron (β⁻) is emitted.
核反应方程需保持总核子数和质子数守恒。α 衰变使 Z 减 2，A 减 4。β⁻ 衰变中，中子转变为质子并放出一个电子（β⁻），因此 Z 加 1，A 不变。
Uses of radioactivity include carbon dating, thickness gauging, cancer therapy (gamma rays), sterilisation and smoke alarms (α particles). Safety precautions involve minimising exposure time, using shielding and maintaining distance.
放射性的应用包括碳年代测定、厚度测量、癌症治疗（γ 射线）、灭菌和烟雾报警器（α 粒子）。安全防护措施包括缩短暴露时间、使用屏蔽和保持距离。
10. Practical Skills and Data Analysis | 实验技能与数据分析
Accurate measurement and uncertainty handling are fundamental in IGCSE Physics practicals. Length, mass, time, current and voltage are commonly measured. The precision of a measuring instrument is typically half the smallest scale division.
精确测量和不确定度处理是 IGCSE 物理实验的基础。常测量的量包括长度、质量、时间、电流和电压。测量仪器的精度通常为最小刻度的一半。
When plotting graphs, use appropriate scales, label axes with quantities and units, and draw a line of best fit (not necessarily through all points). The gradient and intercept often yield physical quantities such as acceleration or resistance.
绘制图表时，要选取合适的标度，标注轴对应的物理量和单位，并画出最佳拟合线（不一定经过所有点）。斜率和截距常可求出加速度、电阻等物理量。
scillation. Plotting T² against length yields a straight line through the origin if T = 2π√l/g. For spring experiments, extension ∝ load up to the limit of proportionality (Hooke's law).
单摆实验中，周期 T 是一次全振动的时间。若 T = 2π√l/g，则 T² 与摆长 l 成正比，图像为过原点的直线。弹簧实验中，在弹性限度内，伸长量与负荷成正比（胡克定律）。
In electrical experiments, always place voltmeters in parallel and ammeters in series. Take repeat readings to minimise random errors and identify anomalies. Systematic errors arise from zero errors or calibration faults and affect all readings consistently.
电学实验中，电压表必须并联，电流表必须串联。需重复读数以减少随机误差并识别异常值。系统误差来自零点误差或校准错误，对所有读数产生一致影响。
Exam papers often include describing patterns from data, calculating quantities using given formulas, and evaluating the reliability of conclusions. Always quote answers to an appropriate number of significant figures and include units.
考试常要求描述数据规律、利用给定公式计算物理量，并评估结论的可靠性。答案应使用适当有效数字并附单位。
11. Space Physics – Earth and the Solar System | 空间物理 – 地球与太阳系
Earth rotates on its axis once every 24 hours causing day and night, and revolves around the Sun once in 365.25 days, giving rise to seasons. The Moon orbits Earth approximately every 28 days, exhibiting phases from new moon to full moon.
地球每 24 小时自转一周，形成昼夜；每年 365.25 天绕太阳公转一周，产生季节。月球约 28 天绕地球一圈，呈现从新月到满月的月相变化。
The Solar System consists of the Sun, eight planets, dwarf planets, moons, asteroids and comets. Planets closer to the Sun have shorter orbital periods. Gravitational force provides the centripetal force necessary for orbital motion.
太阳系包括太阳、八颗行星、矮行星、卫星、小行星和彗星。越接近太阳的行星公转周期越短。万有引力提供轨道运动所需的向心力。
bital radius and T is period. For a circular orbit, the gravitational force equals mv²/r, where m is the mass of the orbiting body.
轨道天体的速率可用 v = 2πr/T 计算，r 为轨道半径，T 为周期。在圆轨道运动中，万有引力等于向心力 mv²/r，m 为天体质量。
Stars evolve over billions of years. Our Sun is a main-sequence star that will eventually become a red giant and then a white dwarf. More massive stars may end as supernovae, leaving behind neutron stars or black holes.
恒星的演化持续数十亿年。太阳是一颗主序星，最终将变成红巨星，然后成为白矮星。质量更大的恒星可能以超新星爆发结束，留下中子星或黑洞。
The universe is all of space and time, and galaxies are vast collections of stars. The Big Bang theory suggests the universe began from an extremely hot and dense point about 13.8 billion years ago and has been expanding ever since, supported by red-shift observations.
宇宙是所有空间和时间的总称，星系是庞大的恒星集合。大爆炸理论认为宇宙起源于约 138 亿年前一个极高温高密的点并持续膨胀至今，红移观测为此提供了证据。
12. Exam Strategies and Common Misconceptions | 考试策略与常见误区
Many candidates lose marks by not reading the question carefully. Pay attention to command words like 'state', 'describe', 'explain' and 'calculate'. 'Explain' requires a reason or cause, often using a scientific principle.
许多考生因未仔细读题而失分。注意关键词，如 "state"（陈述）、"describe"（描述）、"explain"（解释）和 "calculate"（计算）。"Explain" 要求说明原因，常需运用科学原理。
Common misconception: objects in motion require a continuous forward force. In fact, in the absence of net external force, an object moves with constant velocity (Newton's first law). Another misconception: heavier objects fall faster; all objects fall with the same acceleration g in the absence of air resistance.
常见误区：运动的物体需要持续向前的力。实际上，不受外力时物体将匀速运动（牛顿第一定律）。另一个误区：重物落得更快；忽略空气阻力时，所有物体以相同加速度 g 下落。
Students often confuse mass and weight. Mass is measured in kg and is invariant; weight is a force measured in newtons and depends on g. Also, direct current (d.c.) flows in one direction, whereas alternating current (a.c.) changes direction periodically.
学生常混淆质量和重量。质量单位是千克且不随位置改变；重量是力，单位是牛顿，取决于 g。此外，直流电单方向流动，交流电周期性改变方向。
In circuit analysis, always check that the total e.m.f. equals the sum of p.d.s in any closed loop, and current is conserved at junctions. In thermal physics, distinguish between temperature (average kinetic energy) and internal energy (total kinetic and potential energy of all particles).
分析电路时，应检验闭合回路中总电动势等于电势差之和，且节点处电流守恒。热物理中要区分温度（平均动能）和内能（所有粒子的动能与势能总和）。
For the final paper, time management is crucial. Allocate marks roughly to time (e.g., 1 mark per minute). Show working for calculation questions to earn partial credit even if the final answer is wrong.
考试时时间分配至关重要。大致按分值分配时间（如每分钟 1 分）。计算题写清步骤，即使最终答案有误也能获得部分步骤分。
Published by TutorHao | Physics Revision Series | aleveler.com
更多咨询请联系16621398022（同微信）
或截图后用「扫一扫 → 相册」选择本图