📚 Year 8 Cambridge Physics: Key Vocabulary & Terminology Memory Guide | Year 8 Cambridge 物理：关键词汇术语速记指南
Mastering physics starts with a firm grip on the language of the subject. This guide breaks down essential Year 8 Cambridge Physics terms into bite‐size explanations, memory tips, and paired English–Chinese definitions to help you recall keywords quickly and accurately. Use it as a daily revision companion to boost your confidence before tests.
学好物理，从准确理解每一个术语开始。这份指南将 Year 8 Cambridge 物理核心词汇拆解为简洁的中英文解释和记忆窍门，帮助你快速、准确地牢记关键词。把它当作每日复习伙伴，考试前信心倍增。
1. Force and Motion Basics | 力与运动基础
A force is a push or a pull acting on an object, measured in newtons (N). Forces can be contact forces (e.g. friction, tension) or non‑contact forces (e.g. gravity, magnetic force). Think of contact forces as needing a handshake, while non‑contact forces work across empty space.
力是作用在物体上的推或拉，单位是牛顿 (N)。力可分为接触力（如摩擦力、张力）和非接触力（如重力、磁力）。记住：接触力需要“握手”，非接触力隔空就能作用。
Weight is the force of gravity on a mass. It changes with location, unlike mass, which remains the same everywhere. Formula: Weight = mass × gravitational field strength (W = m g). On Earth, g ≈ 10 N/kg.
重量是重力作用在质量上的力，随位置变化。质量则处处相同。公式：重量 = 质量 × 重力场强度 (W = m g)，地球上的 g 约为 10 N/kg。
2. Speed and Motion Graphs | 速度与运动图线
Speed tells you how quickly an object moves. Average speed = total distance ÷ total time. Instantaneous speed is the speed at a specific moment — like looking at a car’s speedometer. In a distance–time graph, a steeper gradient means a higher speed; a flat horizontal line means the object is stationary.
速度表示物体运动的快慢。平均速度 = 总路程 ÷ 总时间。瞬时速度是某一时刻的速度，就像看汽车仪表盘。在距离–时间图中，斜率越陡速度越快；水平线代表物体静止。
Velocity is speed in a given direction. If you turn a corner at the same speed, your velocity changes because the direction changes. This distinction is key when you later study acceleration.
速率是带有方向的速度。保持速率转弯时，速率不变但速度改变，因为方向变了。这个区别对日后学习加速度非常关键。
3. Density and Pressure | 密度与压强
Density = mass ÷ volume. A small, heavy brick is dense; a large, light sponge is not. Remember ρ = m / V — the Greek letter ρ (“rho”) stands for density. Units: kg/m³ or g/cm³.
密度 = 质量 ÷ 体积。一块小而重的砖密度大，一大块海绵密度小。记住 ρ = m / V，ρ 是密度的符号。单位：千克/立方米 或 克/立方厘米。
Pressure s equally in all directions. The unit of pressure is the pascal (Pa), where 1 Pa = 1 N/m².
压强 = 力 ÷ 面积。刀锋利，面积小，压强大。液体和气体中的压强朝各个方向均等作用。压强单位是帕斯卡 (Pa)，1 Pa = 1 N/m²。
4. Energy Forms and Transfers | 能量形式与转移
Energy exists in many forms: kinetic (movement), gravitational potential (height), elastic potential (stretched or compressed), chemical (food, fuel), thermal (heat), sound, light, electrical and nuclear. Energy can be transferred from one form to another or from one object to another, but it is never created or destroyed — the principle of conservation of energy.
能量有多种形式：动能（运动）、重力势能（高度）、弹性势能（拉伸或压缩）、化学能（食物、燃料）、热能、声能、光能、电能和核能。能量可以从一种形式转移成另一种形式，或从一个物体转移到另一个物体，但绝不会凭空产生或消失——能量守恒原理。
A Sankey diagram uses thick or thin arrows to show useful energy output and wasted energy. The wider the arrow, the more energy. Useful tip: wasted energy often ends up as heat.
桑基图用粗细箭头表示有用能和浪费的能量。箭头越宽，能量越多。小窍门：浪费的能量往往最终转化为热能。
5. Work and Power | 功与功率
Work done ion of the force. If you push a wall but it doesn’t move, no work is done in the physics sense, even if you feel tired! The unit of work is the joule (J).
做功 = 力 × 沿力方向移动的距离。推墙而墙不动，物理上不做功，虽然你觉得累！功的单位是焦耳 (J)。
Power is the rate of doing work: power = work done ÷ time taken. A more powerful machine does the same work in less time. Power is measured in watts (W), where 1 W = 1 J/s.
功率是做功的快慢：功率 = 做功 ÷ 所用时间。功率越大的机器，完成同样的功耗时越短。功率单位是瓦特 (W)，1 W = 1 J/s。
6. Particle Theory and States of Matter | 粒子理论与物质状态
All matter is made of tiny particles that are constantly moving. In solids, particles are tightly packed in a regular pattern and can only vibrate in place. In liquids, particles are close together but can flow past one another. In gases, particles are far apart and move freely at high speeds.
所有物质都由不断运动的微小粒子构成。固体中，粒子紧密排列，只能原地振动。液体中，粒子彼此靠近但能相互滑动。气体中，粒子相距很远，高速自由运动。
The spaces between particles explain why solids have a fixed shape, liquids take the shape of their container, and gases fill the whole space available. Remember: more heat energy makes particles vibrate or move faster.
粒子间的间距解释了为何固体有固定形状，液体随容器变形，气体则充满整个空间。记住：给予更多热量，粒子振动或运动就会加快。
7. Changes of State | 物态变化
Melting (solid → liquid) and freezing (liquid → solid) happen at the same temperature — the melting point. Boiling occurs throughout a liquid at a specific temperature, while evaporation happens only at the surface at any temperature. Condensation is gas → liquid. Sublimation (solid → gas) and deposition (gas → solid) skip the liquid stage, like dry ice turning directly into CO₂ gas.
熔化（固→液）和凝固（液→固）发生在同一温度——熔点。沸腾是液体内部和表面同时发生的剧烈汽化，只在特定温度进行；蒸发则在任何温度下只在液面发生。液化（气→液）。升华（固→气）和凝华（气→固）跳过液态，例如干冰直接变为二氧化碳气体。
During a change of state, the temperature stays the same even though heat is being added or removed. This hidden energy is called latent heat.
在物态变化过程中，即使加热或冷却，温度保持不变。这一部分隐藏的能量称为潜热。
8. Wave Basics | 波的基础
A wave is a disturbance that transfers energy from one place to another without transferring matter. Key measurements: amplitude (maximum displacement from rest), wavelength (distance between two identical points on consecutive waves), frequency (number of complete waves per second, measured in hertz, Hz), and period (time for one complete wave, period = 1 / frequency).
波是一种传播能量而不传播物质的扰动。核心参量：振幅（离开平衡位置的最大位移）、波长（相邻两个相同点之间的距离）、频率（每秒完整波的个数，单位赫兹 Hz）和周期（一个完整波所需时间，周期 = 1 / 频率）。
In transverse waves (e.g. light, water ripples), vibrations are perpendicular to the direction of energy travel. In longitudinal waves (e.g. sound), vibrations are parallel to the direction of travel. Think of the “S” in tranSverse for side‑to‑side movement.
横波（如光、水波）的振动方向与能量传播方向垂直。纵波（如声波）的振动方向与传播方向平行。记住横波的“横”有横向之意。
9. Sound and Light | 声音与光
Sound is a longitudinal wave that needs a medium (solid, liquid or gas) to travel; it cannot pass through a vacuum. Echo is a reflected sound wave. The speed of sound in air is about 330 m/s, much slower than light.
声音是一种纵波，需要介质（固、液、气）传播，不能在真空中传播。回声是反射回来的声波。空气中声速约为 330 m/s，远慢于光速。
Light travels in straight lines and can be reflected (bounces off surfaces) and refracted (bends when passing from one medium to another). Dispersion splits white light into a spectrum of colours — remember “Richard Of York Gave Battle In Vain” for red, orange, yellow, green, blue, indigo, violet.
光沿直线传播，可发生反射（从表面弹回）和折射（穿入另一介质时偏折）。色散把白光分解成七色光谱——用“红橙黄绿蓝靛紫”记顺序。
10. Electricity and Magnetism | 电与磁
Electric current is the flow of charged particles, usually electrons, around a circuit. It is measured in amperes (A). Voltage (potential difference) pushes the current; measured in volts (V). Resistance (ohms, Ω) opposes the flow. A simple relationship: Voltage = Current × Resistance (V = I R).
电流是带电粒子（通常是电子）在电路中的流动，单位为安培 (A)。电压（电势差）推动电流，单位为伏特 (V)。电阻（欧姆，Ω）阻碍电流。简单关系：电压 = 电流 × 电阻 (V = I R)。
A series circuit has only one loop; if one bulb breaks, current stops everywhere. A parallel circuit has multiple branches; a break in one branch leaves the others working. Magnets have north and south poles; like poles repel, unlike attract. An electromagnet is a coil of wire (solenoid) with an iron core that becomes magnetic when current flows.
串联电路只有一条回路，一盏灯坏则全路不通；并联电路有多条分支，一条支路断开不影响其他支路。磁铁有南北极，同性相斥、异性相吸。电磁铁是绕在线圈中的铁芯，通电后产生磁性。
11. Memory Boosters in Physics | 物理记忆小窍门
Use acronyms: for the energy forms try “Kids Go Crying To School Loudly Every Night” (Kinetic, Gravitational potential, Chemical, Thermal, Sound, Light, Electrical, Nuclear). Link new words to pictures — draw a tiny particle diagram for solids, liquids and gases. Say the term aloud while writing its definition; hearing yourself reinforces memory. Quiz a friend by giving the definition and asking for the word, then swap.
善用英文首字母串记：能量形式用“K G C T S L E N”。把新词和图画联系起来——为固体、液体和气体画粒子示意图。边写定义边大声念出术语，听觉反馈强化记忆。与朋友互相考问，给出定义让对方猜词，然后互换角色。
Write key formulas on sticky notes and place them on your wall. Group related terms — density, mass, volume — and study them together. The more senses you engage, the stronger the memory.
把关键公式写在便利贴上，贴在墙上。把相关术语（密度、质量、体积）归类一起学习。调动的感官越多，记忆越深刻。
12. Quick‐fire Test Yourself | 自测快问快答
Try to answer these without looking: (1) What is the unit of force? (2) Does weight or mass stay the same on the Moon? (3) Name two non‑contact forces. (4) What does the gradient of a distance–time graph represent? (5) Write the formula linking density, mass and volume. (6) Give one example of a longitudinal wave. (7) What is an electromagnet? (8) State the principle of conservation of energy.
尝试不看答案回答：(1) 力的单位是什么？(2) 在月球上重量和质量哪个不变？(3) 说出两种非接触力。(4) 距离–时间图的斜率代表什么？(5) 写出密度、质量和体积的关系式。(6) 举一个纵波的例子。(7) 什么是电磁铁？(8) 陈述能量守恒原理。
Check your answers against the sections above. If you got any wrong, read that section again and retest tomorrow. Consistent short recall sessions beat last‑minute cramming.
对照上文检查答案。如果有错，重读该小节，明天再测。持续短时记忆练习远比考前突击有效。
Published by TutorHao | Physics Revision Series | aleveler.com
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