Year 7 Cambridge Physics: Exam Techniques and Marking Criteria | 七年级剑桥物理：答题技巧与评分标准

📚 Year 7 Cambridge Physics: Exam Techniques and Marking Criteria | 七年级剑桥物理：答题技巧与评分标准

This guide provides essential exam techniques and a clear understanding of how marks are awarded in Year 7 Cambridge Physics. By learning to read questions carefully, present your working logically, and avoid common errors, you can significantly boost your performance. We will explore the types of questions you may encounter, what examiners expect, and practical strategies to earn every possible mark.

本指南为你介绍七年级剑桥物理考试的核心答题技巧与评分标准。学会仔细审题、条理清晰地展示解题过程并避开常见错误，你可以大幅度提升成绩。我们将探讨可能遇到的题型、考官的期望以及获得每一分的实用策略。

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1. Understanding Command Words | 理解指令词

Every question contains command words that tell you exactly what to do. Common words in Cambridge Physics include ‘state’, ‘describe’, ‘explain’, ‘calculate’, ‘compare’, and ‘suggest’. Misreading these can cost you marks even if you know the science. For example, ‘state’ requires a short, factual answer, while ‘explain’ asks you to give reasons using scientific principles.

每道题都包含指令词，它们明确要求你做什么。剑桥物理中常见的指令词有“state”（陈述）、“describe”（描述）、“explain”（解释）、“calculate”（计算）、“compare”（比较）和“suggest”（建议）。误读这些词会导致失分，即使你懂得相关知识。例如，“state”要求简短的事实性回答，而“explain”则要求使用科学原理给出原因。

• Circle or underline the command word before you start writing.

  动笔前圈出或划出指令词。

• Practise turning a ‘describe’ question into bullet points: what you see, not why.

  练习将“describe”题转换成要点：只写你观察到的现象，不解释原因。

• For ‘explain’, always link back to a key idea like forces or energy transfer.

  遇到“explain”时，始终联系到某个关键概念，如力或能量传递。

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2. Showing Your Working | 展示计算步骤

In calculation questions, marks are often awarded for the method, even if the final answer is incorrect. Always write down the formula you intend to use, substitute the numbers carefully, and then calculate the answer. A clear layout helps the examiner follow your thinking and award partial marks.

在计算题中，过程分通常比答案分更可靠。即便最终答案错了，只要方法正确就能得分。务必写出你使用的公式，仔细代入数字，再计算出结果。清晰的书写让考官能追踪你的思路并给出方法分。

Step 步骤	Example for speed = distance / time 例如：速度 = 距离 / 时间	Marks typically gained 通常得分
1. Write the formula 写出公式	speed = distance / time 速度 = 距离 / 时间	1 mark 1 分
2. Substitute values 代入数值	speed = 100 m / 20 s 速度 = 100 米 / 20 秒	1 mark 1 分
3. Calculate and add unit 计算并加单位	speed = 5 m/s 速度 = 5 米/秒	1 mark (answer) + 1 mark (unit) 1 分（答案）+ 1 分（单位）

Use the triangle method to rearrange simple formulas like weight = mass × gravitational field strength. If you show the rearrangement step, you protect yourself from arithmetic errors.

对于 weight = mass × g 这样的简单公式，可以用三角形法进行变形。如果你写出移项过程，就能避免因运算错误而全题失分。

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3. Using Correct Units | 使用正确的单位

Units are not an afterthought — they are part of the answer. A numerical value without the correct unit, or with an incorrect unit, usually loses a mark. In Year 7 Physics, you will frequently use metres (m), seconds (s), metres per second (m/s), newtons (N), kilograms (kg), joules (J), and degrees Celsius (°C).

单位绝不是附加物——它是答案的一部分。没有写单位或单位错误通常会被扣分。七年级物理中常用的单位有米（m）、秒（s）、米每秒（m/s）、牛顿（N）、千克（kg）、焦耳（J）和摄氏度（°C）。

• Always check whether the question provides data in the unit you need. Convert if necessary (e.g., minutes to seconds).

  始终检查题目所给数据的单位是否与所求单位一致。必要时进行换算（比如将分钟换算成秒）。

• Write the unit on the same line as the final answer, not in brackets later.

  将单位与最终答案写在同一行，不要事后再加括号。

• For derived units like speed, use the slash format m/s or write m s⁻¹ — the examiner accepts both.

  对于像速度这样的导出单位，可用斜线格式 m/s 或写作 m s⁻¹，考官两种都接受。

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4. Interpreting Graphs and Charts | 解读图表

Many questions in Cambridge Physics require you to read information from bar charts, line graphs, and tables. To gain full marks on graph interpretation, you need to describe the trend using data and then explain the trend using science.

剑桥物理很多题目要求你从条形图、折线图和表格中读取信息。要在图表题上拿满分，你需要用数据描述变化趋势，然后用科学原理加以解释。

• When describing a line graph, mention what happens to the dependent variable as the independent variable increases. For example: ‘As the mass increased, the length of the spring increased.’

  描述折线图时，要说明随着自变量的增大，因变量如何变化。例如：“随着质量增加，弹簧的长度也增加。”

• Include numbers from the graph to support your description, e.g., ‘… from 20 g to 60 g, the length doubled from 4 cm to 8 cm.’

  引用图表中的数据来支持你的描述，例如：“……质量从 20 克增加到 60 克，长度从 4 厘米翻倍到 8 厘米。”

• Do not stop at describing; if asked ‘why’, link to a concept like Hooke’s law or friction.

  不要停留在描述层面；如果问到“为什么”，要联系胡克定律或摩擦力等概念。

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5. Writing Clear Explanations | 写出清晰的解释

Explaining a phenomenon in physics means building a logical chain: cause → effect → scientific reason. For instance, when asked why a ball falls faster on Jupiter than on Earth, your answer should state the cause (stronger gravity), the effect (greater acceleration), and the reason (gravity pulls harder).

物理中的解释意味着建立一个逻辑链条：原因 → 结果 → 科学原因。例如，当问到为什么一个球在木星上下落得比在地球上快时，你的回答应该说明原因（引力更强）、结果（加速度更大）和科学理由（引力拉得更用力）。

A strong explanatory answer often uses connectives such as ‘because’, ‘therefore’, ‘so’, and ‘this means that’. Practise writing two-sentence explanations: sentence one gives the outcome, sentence two gives the scientific reason.

出色的解释性答案常常使用“因为”“因此”“所以”“这意味着”等连接词。练习写出两句话的解释：第一句给出结果，第二句给出科学理由。

• For questions on energy, always mention the energy store at the start and the transfer pathway.

  对于能量相关的问题，总是要在一开始就提到能量的储存方式和传递途径。

• Use key vocabulary correctly: words like ‘force’, ‘pressure’, ‘density’, ‘conduct’ must be spelled and applied accurately.

  正确使用关键术语：像“force”“pressure”“density”“conduct”等词必须拼写正确并准确运用。

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6. Tackling Multiple-Choice Questions | 处理选择题

Multiple-choice questions test precision and your ability to eliminate distractors. Cambridge papers often include four options, and the wrong choices are carefully designed to catch common misconceptions. Read all options before selecting your answer.

选择题考查精确度和排除干扰项的能力。剑桥试卷通常包含四个选项，错误选项被精心设计以捕捉常见的错误概念。阅读完所有选项再做选择。

• Cross out obviously wrong options first; this reduces the chance of a careless mistake.

  先划掉明显错误的选项，这能降低粗心出错的几率。

• Watch out for absolute words like ‘always’, ‘never’, or ‘only’—they often make a statement false in physics.

  提防像“总是”“绝不”“只”这样的绝对词——在物理中，含有这些词的陈述常常是错误的。

• If two options are opposite, one is often the correct answer. Use your physics knowledge to decide.

  如果两个选项意思相反，通常其中之一是正确答案，用你的物理知识来判断。

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7. Designing Experiments | 设计实验

You may be asked to plan an investigation, list apparatus, identify variables, or suggest improvements. The examiner looks for a fair test: only the independent variable is deliberately changed, all other variables are controlled, and the dependent variable is measured accurately.

你可能会被要求设计实验、列出器材、确定变量或提出改进建议。考官想要看到的是公平实验：只有自变量被有意识地改变，其他变量都控制不变，因变量被准确测量。

• Start your plan by identifying the independent, dependent, and control variables clearly. Write them in a table if helpful.

  制定计划前，先明确识别自变量、因变量和控制变量。如有必要，可以用表格列出来。

• Mention steps to increase reliability, such as repeating measurements and calculating an average.

  提及提高可靠性的步骤，比如重复测量并计算平均值。

• For ‘improve the experiment’ questions, suggest using more precise instruments (e.g., a digital stopwatch instead of a wall clock) or taking more readings.

  对于“改进实验”这类问题，可以建议使用更精密的仪器（例如用电子秒表代替挂钟），或者增加读数次数。

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8. Common Pitfalls to Avoid | 常见错误及避免方法

Even strong students lose marks by making avoidable mistakes. One frequent error is confusing mass and weight: mass is measured in kg and stays the same everywhere; weight is a force measured in newtons and changes with gravity.

即使成绩好的学生也会因为一些可以避免的错误而失分。一个常见错误是混淆质量和重量：质量以千克为单位，处处相同；重量是力，以牛顿为单位，会因重力变化而改变。

• Misreading a scale: always check the increment on the axis. If the scale goes up in 2s, do not read it as 1s.

  读错刻度：务必检查坐标轴上的刻度间隔。如果每格代表 2，不要误读成 1。

• Omitting the direction arrow when drawing forces. A force arrow must start from the point of application, show direction, and be labelled.

  画力的时候漏掉方向箭头。力的箭头必须从作用点起画，标明方向并标注名称。

• Giving too much information: a ‘state’ question does not need an explanation. Adding unnecessary details wastes time and may introduce an error.

  提供过多信息：“陈述”题不需要解释。加上不必要的细节既浪费时间，还可能引入错误。

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9. How Marks Are Awarded | 评分标准解析

Understanding how examiners allocate marks allows you to tailor your answers. In Cambridge Lower Secondary Physics, each mark corresponds to a specific piece of information or skill shown. Marks can be for correct recall, application of knowledge, or handling data.

了解考官如何分配分数有助于你调整答题方式。在剑桥初中物理中，每一分都对应一个特定的信息点或所展示的技能。分数可能给在正确回忆知识、知识应用或数据处理上。

Question type / 题型	What earns a mark / 如何得分	Common mark allocation / 通常分值
Recall (state, name) 回忆类（陈述、命名）	Correct fact or term given 给出正确的事实或术语	1 mark 1 分
Description (describe) 描述类	Accurate description of pattern or process; may require two points 准确描述规律或过程；可能需要写出两点	2 marks 2 分
Explanation (explain) 解释类	Cause-and-effect chain with scientific reasoning 有科学推理的因果链	2–3 marks 2–3 分
Calculation 计算题	Working, substitution, answer, unit 步骤、代入、答案、单位	2–4 marks 2–4 分

Notice that in extended questions, a single error in the first part does not automatically lose all later marks, if your method is still valid. This is called ‘error carried forward’ (ECF). Always continue working through a problem even if you are unsure of an intermediate result.

请注意，在扩展题中，如果方法仍然有效，即使第一部分出错，后续也未必全扣分。这叫做“错误延续”（ECF）。即使对中间结果不确定，也永远要继续完成题目。

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10. Using Mark Schemes to Self-Assess | 利用评分方案自我评估

After completing a practice paper, never just check your total score. Go through the mark scheme question by question and write down exactly what the examiner required. Compare your answer to the model answer and note any missing keywords or steps. This method dramatically improves future performance.

做完一套练习卷后，绝不只要看总分。要逐题对照评分方案，写下考官到底要求什么。将你的答案与标准答案进行对比，并备注缺失的关键词或步骤。这种方法能极大提升日后的表现。

• Make a list of the command words you lost marks on. Revise the meaning of each.

  把导致你失分的指令词列一个清单，复习每个词的含义。

• Pay attention to the points at which the mark scheme says ‘accept’ or ‘reject’. Some correct answers are not the ones you expected.

  留意评分方案中写“可接受”或“不接受”的地方。有些正确答案可能不是你设想的那样。

• Write a corrected version of your answer in green pen to reinforce the right model.

  用绿色笔写出修正后的答案，以强化正确的答题模式。

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11. Time Management in Exams | 考试中的时间管理

In a 45-minute Cambridge Year 7 Physics paper, you have roughly 1 minute per mark. A 3-mark question deserves about 3 minutes. If you get stuck on a question, mark it with a star and move on. Come back later with fresh eyes. Finishing the paper gives you a chance at many easy marks, while spending 10 minutes on one difficult question may just gain 2 marks.

在一份 45 分钟的七年级剑桥物理试卷中，大约每分钟要对应 1 分。一道 3 分题值得花约 3 分钟。如果卡在某道题上，用星号标记后跳过，之后再回头做。完成全卷能让你拿到许多容易得的分，而在难题上花 10 分钟可能只换来 2 分。

• Read through the whole paper in the first 2 minutes to spot easy questions and plan your sequence.

  头 2 分钟快速浏览全卷，找出容易的题目并规划答题顺序。

• For multi-part questions, read all parts before answering. Often part (b) gives clues to part (a).

  对于多小问的题，先读完所有小问再作答。通常 (b) 问会给 (a) 问提供线索。

• Leave 5 minutes at the end to check units, spelling of key terms, and that you have not missed a question on the reverse side of the page.

  最后留 5 分钟检查单位、关键术语的拼写，并确认没有遗漏背面页的题目。

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12. Checking Your Answers | 检查答案

Checking is not just reading; it is a focused process. Start by verifying that every question has an answer written in the correct space. Then check your calculations by working backwards: put your answer back into the formula to see if you get the original data. For written answers, read them aloud in your head — does the sentence make scientific sense?

检查并不仅仅是阅读，而是一个专注的过程。首先确认每道题的答案都写在了正确位置。然后通过逆向验算来检查计算题：把你的答案代回公式中，看能否得到原始数据。对于文字题，在心里默读一遍——这个句子在科学上说得通吗？

• Double-check any conversion factors you used. Did you change minutes to seconds? Did you convert grams to kilograms?

  重新检查你用到的所有换算系数。分钟换算成秒了吗？克换算成千克了吗？

• For graphs, ensure you labelled both axes with quantities and units. Also check that your plotted points are correct and the line of best fit is straight or curved as the data suggests.

  对于图表题，确保两个轴都标注了物理量和单位。同时检查描点是否正确，最佳拟合线是否根据数据趋势画成直线或曲线。

• If you have time, rewrite any hastily written numbers clearly. A ‘7’ that looks like a ‘1’ can cost a mark.

  如果有时间，把潦草书写下的数字重新写清楚。把“7”写成“1”的样子可能会丢分。

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Published by TutorHao | Physics Revision Series | aleveler.com

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