📚 Year 7 WJEC Physics: In-Depth Analysis of Past Paper Questions | Year 7 WJEC 物理：历年真题深度解析
Welcome to this detailed walkthrough of typical WJEC Year 7 Physics past paper questions. By analysing real exam-style problems, we can identify common themes, key command words, and the exact steps needed to secure full marks. Whether it is calculating speed, describing energy transfers, or predicting circuit behaviour, this guide will sharpen your exam technique and boost your confidence. Each section below pairs the physics with the marking habits that examiners actually reward, so you can revise smarter rather than simply longer.
欢迎来到 WJEC 七年级物理历年真题深度解析。通过分析真实的考试题型，我们可以总结出常考主题、核心指令词以及拿到满分所需的具体步骤。无论是计算速度、描述能量转移还是预测电路行为，这份指南都会磨练你的考试技巧并增强你的自信心。下文每一节都把物理知识点与考官真正给分的评分习惯配对讲解，让你复习得更聪明，而不是单纯更久。
1. How to Read WJEC Command Words | 如何解读 WJEC 指令词
Command words decide how many marks are available and what kind of answer is expected. In WJEC papers the most common ones are state, calculate, describe, explain, compare and suggest. 'State' needs a single fact with no reasoning, while 'explain' always requires a cause-and-effect link, usually signalled by the word because.
指令词决定了这道题值多少分、期望你答什么。WJEC 试卷中最常见的是 state（陈述）、calculate（计算）、describe（描述）、explain（解释）、compare（比较）和 suggest（提出）。state 只需给出一个事实，不需要推理；而 explain 一定需要因果联系，通常用 because 来体现。
| Command word | What to write | 中文说明 |
| State / Give | One short fact or value | 一句事实或数值 |
| Calculate | Formula, substitution, answer with unit | 公式、代入、带单位答案 |
| Describe | What happens, in order | 按顺序说明发生了什么 |
| Explain | Reason using because / so | 用 because / so 给出原因 |
| Compare | Both similarities and differences | 相同点与不同点都要写 |
| Suggest | A sensible idea using physics you know | 运用所学物理提出合理想法 |
A very common mistake is writing three sentences for a one-mark 'state' question and running out of time. Equally common is writing a single word for a three-mark 'explain' question. Match the length of your answer to the number of marks and the command word.
最常见的失分方式有两种：一分题 'state' 写了一整段，浪费时间；三分题 'explain' 只写一个词。请依据分值大小和指令词来决定答案的长短。
2. Speed, Distance and Time Calculations | 速度、距离与时间计算
rearrange it to find any unknown and always include the correct unit, typically metres per second (m/s).
七年级最常考查的技能之一是使用公式 速度 = 距离 ÷ 时间。你必须能够变形公式求出任意未知量，并且始终写上正确的单位，通常是米每秒 (m/s)。
p; distance = speed × time time = distance ÷ speed
The triangle method is a quick way to remember all three versions: put distance on the top and speed and time on the bottom, then cover the quantity you want.
用三角形法可以快速记住三个版本：把距离写在上面，速度和时间写在下面，遮住你想求的量即可。
Sample Past Paper Question: A student walks 240 metres to school in 120 seconds. Calculate her average speed. (2 marks)
真题示例： 一名学生步行 240 米去上学，耗时 120 秒。计算她的平均速度。(2 分)
Step 1 – Write down what you know: distance = 240 m, time = 120 s.
步骤 1 – 写下已知量： 距离 = 240 米，时间 = 120 秒。
Step 2 – State the formula and substitute: speed = distance ÷ time = 240 ÷ 120.
步骤 2 – 写出公式并代入： 速度 = 距离 ÷ 时间 = 240 ÷ 120。
Step 3 – Calculate and give the unit: speed = 2 m/s.
步骤 3 – 计算出结果并写上单位： 速度 = 2 m/s。
The formula itself usually earns 1 mark and the correct answer with unit earns the second. Writing only '2' without 'm/s' can lose that second mark, so build the habit of underlining the unit in your final line.
通常写对公式得 1 分，答案正确且带单位再得 1 分。只写 '2' 而不写 'm/s' 可能丢掉这 1 分，所以要养成在最后一行把单位画出来的习惯。
3. Rearranging Formulas and Unit Conversion | 公式变形与单位换算
Many past paper questions hide the difficulty in the units rather than the physics. If a time is given in minutes and a distance in kilometres, you must convert before substituting, otherwise your final answer will be wrong even if the method is perfect.
许多真题的难点其实藏在单位里，而不是物理概念本身。如果时间单位是分钟、距离单位是千米，你必须先换算再代入，否则即使方法完全正确，最终答案也是错的。
- 1 km = 1000 m
- 1 minute = 60 s, 1 hour = 3600 s
- 1 m/s = 3.6 km/h
- 1 cm = 0.01 m, so 1 cm² = 0.0001 m² and 1 cm³ = 0.000001 m³
Worked example: d in m/s. Convert: 9 km = 9000 m and 15 minutes = 900 s. Then speed = 9000 ÷ 900 = 10 m/s.
例题： 一名骑行者 15 分钟行驶 9 千米，求她以 m/s 为单位的速度。换算：9 千米 = 9000 米，15 分钟 = 900 秒。于是 速度 = 9000 ÷ 900 = 10 m/s。
ance ÷ speed you divide. Always check by substituting your answer back into the original formula.
变形公式时要一步一步换主项，不要直接跳到答案。求距离用乘法，求时间用除法。算完后把答案代回原公式检验一下。
4. Distance–Time and Speed–Time Graphs | 距离–时间图像与速度–时间图像
Graph questions appear in almost every WJEC paper. On a distance–time graph, the gradient equals speed; a horizontal line means the object is stationary; a steeper line means greater speed. On a speed–time graph, the gradient equals acceleration and the area under the line equals the distance travelled.
图像题几乎出现在每一份 WJEC 试卷中。在距离–时间图像上，斜率代表速度；水平线表示物体静止；线越陡说明速度越大。在速度–时间图像上，斜率代表加速度，线下面积代表行驶距离。
bsp; acceleration = Δspeed ÷ Δtime distance = area under speed–time graph
Typical question: A car accelerates from 0 m/s to 20 m/s in 8 s. Calculate its acceleration. (2 marks)
典型题目： 一辆汽车在 8 秒内从 0 m/s 加速到 20 m/s，计算加速度。(2 分)
/s². Note the unit: m/s² not m/s, because acceleration is the change in speed each second.
答案：加速度 = 20 ÷ 8 = 2.5 m/s²。注意单位是 m/s² 而不是 m/s，因为加速度表示每秒速度的变化量。
For area questions, split the graph into rectangles and triangles, calculate each area, then add them. Show the split with dotted lines on the graph so the examiner can award the method mark even if your arithmetic slips.
求面积的题目要把图像拆成长方形和三角形，分别求面积后相加。在图上用虚线标出拆分方式，这样即使计算有小错，考官仍可给出方法分。
5. Forces, Free-Body Diagrams and Resultant Force | 力、受力图与合力
Forces are pushes or pulls measured in newtons (N). A free-body diagram shows every force acting on one object as an arrow: the length shows size, the direction shows direction. Forces acting in the same direction are added, and forces in opposite directions are subtracted to give the resultant force.
力是推或拉的作用，单位是牛顿 (N)。受力图把作用在同一物体上的每个力用箭头表示：箭头长度表示大小，方向表示力的方向。同方向的力相加，反方向的力相减，得到合力。
ss × gravitational field strength W = m × g (g ≈ 9.8 N/kg on Earth)
Worked example: e box stays on the ground; the horizontal resultant is 25 N to the right, so the box accelerates.
例题： 一个箱子受到 60 N 向下的重力、25 N 向右的推力。求竖直方向的合力。答：若地面向上支持力也是 60 N，则竖直合力为 0 N，箱子不会离地；水平合力为向右 25 N，所以箱子会加速运动。
A common exam error is forgetting the upward contact force from a table or floor. Every object resting on a surface has a support force that balances its weight, which is why the book on your desk is not accelerating downwards.
常见失分点是不写桌面或地面的向上支持力。任何静止放在表面上的物体都受到一个与其重力平衡的支持力，这正是桌上的书没有向下加速的原因。
6. Energy Stores, Transfers and Conservation | 能量储存、转移与守恒
WJEC expects you to name energy stores rather than simply saying 'energy'. Useful stores include kinetic, gravitational potential, elastic potential, thermal, chemical and nuclear. Between stores, energy is transferred mechanically, electrically, by heating or by radiation.
WJEC 要求你写出具体的能量储存形式，而不是笼统地说 'energy'。常用的储存形式包括动能、重力势能、弹性势能、热能、化学能和核能。能量在这些储存之间通过做功、电流、加热或辐射的方式转移。
- Kinetic store: anything moving | 动能：任何运动的物体
- Gravitational potential store: anything raised above the ground | 重力势能：任何被抬高的物体
- Elastic potential store: a stretched or squashed spring | 弹性势能：被拉伸或压缩的弹簧
- Thermal store: anything hot | 热能：任何温度较高的物体
- Chemical store: food, fuels, batteries | 化学能：食物、燃料、电池
energy = ½ × m × v² efficiency = useful output ÷ total input × 100%
Typical question: Describe the energy transfers when a ball is dropped and bounces. (3 marks)
典型题目： 描述小球下落并弹起时的能量转移。(3 分)
Model answer: the ball starts with a gravitational potential store; as it falls this is transferred to a kinetic store; on impact some energy is transferred to a thermal store of the ball and floor by heating, so the ball does not bounce back to its original height. Each transfer named correctly is worth a mark.
参考答案：小球最初具有重力势能储存；下落过程中转移到动能储存；撞击时一部分能量通过加热转移到小球和地面的热能储存，所以小球弹不回原来高度。每写对一个转移环节得 1 分。
7. Electric Circuits: Series and Parallel | 电路：串联与并联
Circuit questions test whether you can predict how current and voltage behave in different arrangements. In a series circuit there is one path, so the current is the same everywhere and the supply voltage is shared between components. In a parallel circuit there is more than one path, so the current splits and the voltage across each branch is the same.
电路题考查你能否预测不同连接方式下电流和电压的变化。串联电路只有一条路径，因此各处电流相同，电源电压被各元件分配。并联电路有多条路径，因此电流会分流，而各支路两端的电压相同。
| Quantity | Series | Parallel |
| Current | Same everywhere | Splits between branches |
| Voltage | Shared between components | Same across each branch |
| If one bulb breaks | Whole circuit stops | Other branches still work |
Ammeters are connected in series with a component and voltmeters in parallel with it. This is a favourite exam trap: a student who connects the ammeter in parallel will usually score zero for the circuit diagram even if their numerical answer is right.
电流表要与元件串联，电压表要与元件并联。这是考试中最常见的一个陷阱：把电流表并联连错的同学，即使后面数值算对，电路图那部分通常也拿不到分。
8. Ohm's Law and Charge Calculations | 欧姆定律与电荷计算
Ohm's law links voltage, current and resistance for a component kept at constant temperature. Once you know two of the three quantities, the third can be calculated. Charge calculations are equally common and simply ask how much charge flows in a given time.
欧姆定律把电压、电流和电阻联系起来，前提是元件温度保持不变。三个量中已知两个，就能求出第三个。电荷计算同样高频，本质是求在一定时间内流过多少电荷。
;V = I × R charge = current × time Q = I × t
Worked example: rrent of 0.5 A through it. Find the voltage across it. Answer: V = I × R = 0.5 × 12 = 6 V.
例题： 一个 12 Ω 的电阻中电流为 0.5 A，求它两端的电压。答：V = I × R = 0.5 × 12 = 6 V。
Second example: f 2 A flows for 30 s. Calculate the charge transferred. Answer: Q = I × t = 2 × 30 = 60 C.
第二例： 2 A 的电流持续 30 秒，计算转移的电荷量。答：Q = I × t = 2 × 30 = 60 C。
Remember that the ohm (Ω) is the unit of resistance and the coulomb (C) is the unit of charge. Writing the correct unit is often worth a separate mark, and it is the cheapest mark in the whole paper.
记住电阻的单位是欧姆 (Ω)，电荷的单位是库仑 (C)。写对单位往往单独给分，这是整张卷子里最容易拿到的一分。
9. Density, Pressure and Moments | 密度、压强与力矩
These three topics share one feature: they all test your ability to substitute into a formula and handle units carefully. Density compares mass with volume, pressure compares force with area, and the moment of a force compares the force with its perpendicular distance from the pivot.
这三个主题有一个共同点：都考查代入公式的能力以及对单位的细心程度。密度比较质量与体积，压强比较力与面积，力矩则比较力与它到支点的垂直距离。
; pressure = force ÷ area moment = force × distance from pivot
- Density unit: kg/m³ or g/cm³ | 密度单位：kg/m³ 或 g/cm³
- Pressure unit: N/m² or pascal (Pa) | 压强单位：N/m² 或帕斯卡 (Pa)
- Moment unit: newton metre (N m) | 力矩单位：牛顿米 (N m)
Typical question: 0 cm³. Calculate its density. Answer: 600 ÷ 200 = 3 g/cm³, or 3000 kg/m³ after conversion.
典型题目： 一块质量 600 g 的物块体积为 200 cm³，求其密度。答：600 ÷ 200 = 3 g/cm³，换算后为 3000 kg/m³。
For moments, examiners look for the word perpendicular. A force of 20 N acting 0.4 m from a pivot gives a moment of 8 N m only if the distance is measured at right angles to the force line.
在力矩题中，考官特别关注 perpendicular（垂直）这个词。20 N 的力作用在距支点 0.4 m 处，只有当距离是沿力的垂直方向测量时，力矩才等于 8 N m。
10. Waves: Sound and Light Basics | 波：声与光基础
Year 7 wave questions focus on describing rather than calculating, but the wave equation still appears. Sound needs a medium and cannot travel through a vacuum, whereas light can. Sound travels faster in solids than in gases because the particles are closer together.
七年级的波部分以描述为主而非计算，但波速公式仍会出现。声音需要介质，不能在真空中传播，而光可以。声音在固体中的传播速度比在气体中快，因为固体粒子排列更紧密。
wave speed = frequency × wavelength v = f × λ
Frequency is measured in hertz (Hz), wavelength in metres (m), so wave speed comes out in m/s. Amplitude describes loudness for sound and brightness for light, while frequency describes pitch for sound and colour for light.
频率的单位是赫兹 (Hz)，波长的单位是米 (m)，因此波速的单位是 m/s。振幅对声音而言表示响度、对光而言表示亮度；频率对声音而言表示音调、对光而言表示颜色。
Typical question: State two differences between sound waves and light waves. (2 marks)
典型题目： 说出声波与光波的两点不同。(2 分)
Model answer: sound is a longitudinal wave and light is transverse; sound needs a medium but light does not. Notice that compare-style questions reward two clearly linked statements, not two unrelated facts.
参考答案：声波是纵波，光波是横波；声音需要介质，光不需要。注意这类比较题给分的是两条清晰对应的陈述，而不是两个互不相关的事实。
11. Experimental Skills, Tables and Graphs | 实验技能、表格与图表
Practical questions often carry more marks than calculation questions. You are expected to identify the independent variable you change, the dependent variable you measure, and at least one control variable you keep the same to make the test fair.
实验题的分数往往比计算题还多。你需要指出改变的自变量、测量的因变量，以及至少一个保持不变的控变量，以保证实验公平。
- Independent variable: the one you deliberately change | 自变量：你主动改变的量
- Dependent variable: the one you measure | 因变量：你测量得到的量
- Control variables: those kept constant | 控变量：保持不变的量
Table questions reward correct column headings with units, consistent significant figures, and repeated readings averaged to reduce random error. Graph questions reward labelled axes with units, a sensible scale, plotted points and a line of best fit.
表格题给分点在于：列标题正确且带单位、有效数字一致、重复读数取平均以减小随机误差。图像题给分点在于：坐标轴标注且带单位、刻度合理、点绘制准确、画出最佳拟合线。
Always describe how you would reduce error rather than simply stating that the experiment was inaccurate. For example: 'repeat each measurement three times and calculate a mean, then ignore anomalies.' This kind of sentence reliably earns the improvement mark.
描述如何减小误差，而不是只说实验不准确。例如：'每个测量重复三次并取平均，剔除异常值。' 这类句子往往能稳稳拿到改进分。
12. Exam Technique and Revision Plan | 应试技巧与复习计划
Knowing the physics is only half the battle; managing the paper is the other half. Read each question twice, underline the command word and the numbers, and write down the formula before substituting. If you get stuck, move on and return later, because marks are evenly spread across topics.
掌握物理只是成功的一半，另一半是管理好整张试卷。每道题读两遍，划出指令词和数字，先写公式再代入。遇到卡壳先跳过，稍后回来，因为各主题的分值分布比较均匀。
- Week 1: speed, distance, time and graphs | 第 1 周：速度、距离、时间与图像
- Week 2: forces, energy stores and transfers | 第 2 周：力、能量储存与转移
- Week 3: circuits, Ohm's law and charge | 第 3 周：电路、欧姆定律与电荷
- Week 4: density, pressure, moments and waves | 第 4 周：密度、压强、力矩与波
- Week 5: full past papers under timed conditions | 第 5 周：限时完成整套真题
After each paper, mark it yourself using the official mark scheme and colour-code your errors: red for missing physics, amber for calculation slips, green for unit errors. Most students find that unit errors and command-word misreads cost more marks than genuine gaps in understanding.
每做完一套真题，用官方评分标准自己批改，并给错误分类：红色表示物理概念缺失，黄色表示计算失误，绿色表示单位错误。多数学生会发现，单位错误和误读指令词丢的分，比真正不会的知识点还多。
rmula sheet for the night before the exam. If you can write speed, weight, efficiency, Ohm' v = f × λ from memory, you are ready for almost every calculation WJEC can set at Year 7.
最后，准备一张考前一晚看的一页公式表。如果你能默写出速度、重力、效率、欧姆定律、电荷、密度、压强、力矩以及 v = f × λ，那么 Year 7 阶段 WJEC 几乎所有计算题你都准备好了。
Published by TutorHao | Year 7 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