学习目标
- Describe “poles” using evidence from observation, measurement, or a model.
- Describe “attraction” using evidence from observation, measurement, or a model.
- Describe “repulsion” using evidence from observation, measurement, or a model.
Year 3 / Primary Science / Physics foundations / Forces and magnets
Magnetic forces
Magnetic forces: structured theory, worked examples, answered practice, and a mastery checklist for Year 3.
核心概念与检查
- I draw and analyse a circuit with correct instruments.
- I connect charge, current, voltage, resistance, and power.
- Every solution or explanation for “Magnetic forces” should include a method, justification, and final check.
单元
核心理论
练习前按清晰顺序掌握本章核心概念。
Charge, current, and potential difference
Charge is a property, current is charge flow rate, and potential difference is energy per unit charge. Keep these definitions distinct.
Circuit and conservation
Draw a closed circuit with correct symbols. Apply charge conservation at junctions and energy conservation around loops where required.
Fields and induction
Field lines indicate direction and relative strength. In induction, changing magnetic flux is linked to induced potential difference.
poles
For “poles”, start from an observation or model, define quantities and units where relevant, and separate the changed factor from the measured outcome. Support the conclusion with data and state the test's limitations.
attraction
For “attraction”, start from an observation or model, define quantities and units where relevant, and separate the changed factor from the measured outcome. Support the conclusion with data and state the test's limitations.
repulsion
For “repulsion”, start from an observation or model, define quantities and units where relevant, and separate the changed factor from the measured outcome. Support the conclusion with data and state the test's limitations.
Primary Science / Physics foundations
例题讲解
逐步查看方法，并理解每一步为何成立。
Worked enquiry example
In a safe test about “poles”, the first condition gives 14 units and the second 11. Which is greater, and what should be kept the same?
- 1Compare the two measurements.
- 2State the changed factor and the conditions that must stay the same.
- 3Write a conclusion supported only by the data.
The first value is greater by 3 units. A fair test changes only one factor.
Thinking and explanation example
Explain “poles” in your own words and use a picture, objects, a table, or a simple measurement to support it.
- 1State what is known and what is being found.
- 2Choose one clear representation.
- 3Explain what it shows and check that the answer is sensible.
A complete explanation connects the correct idea, a clear representation, and a sensible check.
Magnetic forces
含答案练习
八道分层练习，从基础熟练到考试应用。请先独立完成，再查看提示或答案。
基础熟练3 分钟
Record 9 safe observations about “poles” without writing a conclusion yet.
提示
An observation is something seen, heard, or measured.
答案指南
The response needs 9 specific observable or measurable statements, not guesses about cause.
基础熟练4 分钟
Design a fair test for “attraction”: what changes, what is measured, and which 3 things stay the same?
提示
Change one factor only.
答案指南
Full response: one changed factor, one measurable outcome, and 3 controlled conditions.
应用4 分钟
Measurements are 8, 5, and 13 units. Put them in a table, find the greatest, and the difference from the least.
提示
Use condition and measurement headings.
答案指南
Greatest 13, least 5, difference 8 units.
应用5 分钟
Sort examples of “poles” into two groups and state the sorting rule.
提示
Each item should clearly match one group.
答案指南
A full response gives two named groups, at least two examples in each, and an observable sorting rule.
推理5 分钟
Choose a suitable tool and unit to measure something connected with “attraction”.
提示
Decide whether you measure length, time, mass, temperature, or volume.
答案指南
The quantity, instrument, and unit must match, e.g. time-stopwatch-s or length-ruler-cm.
推理6 分钟
From data 3, 9, 15, predict the next value and explain the pattern.
提示
Look for the constant change +6.
答案指南
21; +6.
考试题型7 分钟
Write 3 safety rules for a simple activity about “poles” and explain the risk each reduces.
提示
Link each rule to a reason.
答案指南
A full response gives 3 specific rules, each linked to a risk, and requires supervision where appropriate.
考试题型8 分钟
Data A=9 and B=14. Write a conclusion, evidence, and one limitation about “attraction”.
提示
Do not claim more than the two values show.
答案指南
B is 5 greater than A. The values support this, but two measurements alone do not prove a general rule.
常见错误
- Connecting an ammeter in parallel or a voltmeter in series.
- Confusing current with voltage or saying current is consumed.
- Ignoring direction in force, field, or induction.
掌握度检查
- I draw and analyse a circuit with correct instruments.
- I connect charge, current, voltage, resistance, and power.
- I interpret fields and induction with direction.
Magnetic forces
章节作业
六道不同作业，从基础到挑战，包含预计用时、提示和答案指南。
基础5 分钟
Homework 1: Record 5 safe observations about “poles” without writing a conclusion yet.
提示
An observation is something seen, heard, or measured.
答案指南
The response needs 5 specific observable or measurable statements, not guesses about cause.
基础6 分钟
Homework 2: Design a fair test for “attraction”: what changes, what is measured, and which 4 things stay the same?
提示
Change one factor only.
答案指南
Full response: one changed factor, one measurable outcome, and 4 controlled conditions.
进阶7 分钟
Homework 3: Measurements are 4, 6, and 10 units. Put them in a table, find the greatest, and the difference from the least.
提示
Use condition and measurement headings.
答案指南
Greatest 10, least 4, difference 6 units.
进阶8 分钟
Homework 4: Sort examples of “poles” into two groups and state the sorting rule.
提示
Each item should clearly match one group.
答案指南
A full response gives two named groups, at least two examples in each, and an observable sorting rule.
挑战10 分钟
Homework 5: Choose a suitable tool and unit to measure something connected with “attraction”.
提示
Decide whether you measure length, time, mass, temperature, or volume.
答案指南
The quantity, instrument, and unit must match, e.g. time-stopwatch-s or length-ruler-cm.
挑战12 分钟
Homework 6: From data 6, 8, 10, predict the next value and explain the pattern.
提示
Look for the constant change +2.
答案指南
12; +2.
35 分钟 / 30 分
完整章节测试
带计时器、完整分值和参考答案的章节自测。
Start the timer when ready, work without notes, show every step, and open model answers only after finishing.
1. Record 3 safe observations about “poles” without writing a conclusion yet.
2 分答案指南
The response needs 3 specific observable or measurable statements, not guesses about cause.
2. Design a fair test for “attraction”: what changes, what is measured, and which 4 things stay the same?
3 分答案指南
Full response: one changed factor, one measurable outcome, and 4 controlled conditions.
3. Measurements are 9, 6, and 15 units. Put them in a table, find the greatest, and the difference from the least.
3 分答案指南
Greatest 15, least 6, difference 9 units.
4. Sort examples of “poles” into two groups and state the sorting rule.
4 分答案指南
A full response gives two named groups, at least two examples in each, and an observable sorting rule.
5. Choose a suitable tool and unit to measure something connected with “attraction”.
4 分答案指南
The quantity, instrument, and unit must match, e.g. time-stopwatch-s or length-ruler-cm.
6. From data 4, 6, 8, predict the next value and explain the pattern.
4 分答案指南
10; +2.
7. Write 4 safety rules for a simple activity about “poles” and explain the risk each reduces.
5 分答案指南
A full response gives 4 specific rules, each linked to a risk, and requires supervision where appropriate.
8. Data A=3 and B=9. Write a conclusion, evidence, and one limitation about “attraction”.
5 分答案指南
B is 6 greater than A. The values support this, but two measurements alone do not prove a general rule.
单元
官方来源与核验
课程参考来源；教学顺序请始终与学校和老师确认。
Primary Science / Physics foundations
Year 3: 数学与物理的结构化路线，包含章节、练习和下一步。
本章覆盖内容
结构跟随教材，用来帮助组织学习。
poles
attraction
repulsion
重点关注
通常容易出错或需要更多复习的部分。
I draw and analyse a circuit with correct instruments.
I connect charge, current, voltage, resistance, and power.
I interpret fields and induction with direction.
来源、日常资料与学习资源
从教材、daily material、PDFs、videos 和 worked examples 开始。
Start from the official textbook or specification referenced on the subject page.
Use the notes and examples as support, not as a replacement for the official syllabus.
Check the current syllabus version before exam preparation.
按小主题练习
进入 full tests 前先做 targeted practice，让覆盖情况更清楚。
Record 9 safe observations about “poles” without writing a conclusion yet.
Design a fair test for “attraction”: what changes, what is measured, and which 3 things stay the same?
Measurements are 8, 5, and 13 units. Put them in a table, find the greatest, and the difference from the least.
Sort examples of “poles” into two groups and state the sorting rule.
Choose a suitable tool and unit to measure something connected with “attraction”.
From data 3, 9, 15, predict the next value and explain the pattern.
Write 3 safety rules for a simple activity about “poles” and explain the risk each reduces.
Data A=9 and B=14. Write a conclusion, evidence, and one limitation about “attraction”.
Mocks 与进度检查
如何衡量本章进度，以及何时加入综合 mock。
Start with untimed practice by subtopic.
Move to a short timed checkpoint only after completing the mastery checklist.
Record each error with the correct method and revisit it after 48 hours.
下一步
完成本章后该做什么，以及它如何连接到下一单元。
Complete the practice without support.
Explain the core method aloud in under two minutes.
Continue to the next chapter or request targeted tutor support.
说明：每学年的正式考试范围请始终以学校、老师和当前官方来源为准。