评分规律
MS 常见标记含义
| 标记 | 含义 |
|---|---|
| B1 | "Basic" mark — 基础得分点 |
| M1 | "Method" mark — 方法得分点 |
| A1 | "Accuracy" mark — 精确度得分点 |
| D1 | "Detail" mark — 细节得分点 |
| B1 × 2 | 两个独立的基础得分点 |
| max 2 | 此部分最多 2 分 |
Defining the Problem 评分规律
B1: IV / DV（1 分）
得分要求：
- 明确写出哪个是 IV，哪个是 DV
- 标准句式：" is the independent variable and is the dependent variable"
- 或者 "vary and measure "
B1: Control Variables（1 分）
得分要求：
- 至少列出 2 个具体的控制变量
- 每个变量用名称+保持方式
- ❌ "keep all other variables constant" — 不得分
- ✅ "keep constant by using the same spring" — 得分
Methods of Data Collection 评分规律
B1: Labelled Diagram
得分要求：
- 装置图必须标注关键部件
- 标注不能是 "thing" / "object"，必须有名称
- 需要显示如何改变 IV 和测量 DV
常见扣分原因：
- 没有标注（unlabelled）
- 标注与文字描述矛盾
- 连线不合理
B1-B4: Procedure
每个 B1 对应一个独立的步骤。常见分配：
| 步骤 | 典型得分点 |
|---|---|
| 改变 IV | "The IV is varied by ..." |
| 测量 DV | "DV is measured using ..." |
| 控制 CV | "CV is kept constant by ..." |
| 测量范围 | "At least 6 readings over a suitable range" |
关于测量范围的关键短语
- "Measurements are taken over a range of ___"
- "At least 6 different values of IV are used"
- "The range covers from ___ to ___"
Method of Analysis 评分规律
B1: Graph type
- 必须给出 x-axis 和 y-axis 的具体量
- ❌ "plot a graph" — 不够具体
- ✅ "plot a graph of against " — 得分
B1: Expected result
- "If the relationship holds, the graph will be a straight line"
- 如果理论要求过原点："passing through the origin"
- 如果有 intercept："with a non-zero intercept"
B1: Constant from graph
- "gradient = ___ , therefore the constant = ___"
- 必须写出用 gradient / intercept 表示常数的完整公式
Additional Detail / Safety 评分规律
D1 - D5：每个细节 1 分
常见的可得分细节：
| 类别 | 具体细节 |
|---|---|
| 重复测量 | "Repeat each measurement and calculate the mean" |
| 检测异常值 | "Check for anomalous results and repeat" |
| 测量小量 | "Measure using a micrometer" |
| 减少误差 | "Use a set square to ensure the ruler is vertical" |
| 安全措施 | "Wear safety goggles to protect eyes from ..." |
| 避免系统误差 | "Zero the balance before use" |
| 额外参数 | "Count the number of turns " |
| 实验条件 | "Ensure the room temperature is constant" |
常见 MS 关键词
| 关键短语 | 出现频率 | 分值 |
|---|---|---|
| vary ... and measure ... | 几乎每份 MS | B1 |
| keep ... constant | 几乎每份 MS | B1 |
| labelled diagram | 几乎每份 MS | B1 |
| at least 6 readings | 常见 | B1 |
| repeat and average | 几乎每份 MS | D1 |
| safety goggles | 常见（弹簧/重物） | D1 |
| straight line | 几乎每份 MS | B1 |
| gradient / intercept | 几乎每份 MS | B1 |
备注
记住：MS 的 B1 是基础分，确保覆盖所有 B1 后再追求 D1。B1 拿满可得 10 分，剩下的 5 分来自 D1 细节。