How to Perform in PSLE | Learner’s Guide Vol 0943 | Science: Explain How a Coloured Filter Transmits Selected Light and Absorbs Other Colours

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1. Start with the incident light

A filter cannot transmit a colour that is absent from the light reaching it. White light contains a broad range of visible colours, while a single-colour source provides a narrower input.

Build the explanation by naming the colours present in the incident light and the filter’s selective transmission and absorption. A remembered keyword is not enough: connect the observation to the mechanism and identify what would have to change for the conclusion to change.

Repair the nearest misconception by checking the light reflected by the object after filtering and returning to source filter object observer order brightness controls and cautious colour claims. State why the tempting alternative is too strong, incomplete or about a different stage.

• Check the colours present in the incident light.
• Check the filter’s selective transmission and absorption.
• Check the light reflected by the object after filtering.
• Check source filter object observer order brightness controls and cautious colour claims.

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CHAPTER 2 OF 12 · Back to contents

2. Describe selective transmission

An idealised red filter transmits red light well and absorbs much of the other visible light. Real filters may transmit ranges imperfectly, so classroom explanations should state the simplified model when used.

Build the explanation by naming the colours present in the incident light and the filter’s selective transmission and absorption. A remembered keyword is not enough: connect the observation to the mechanism and identify what would have to change for the conclusion to change.

Repair the nearest misconception by checking the light reflected by the object after filtering and returning to source filter object observer order brightness controls and cautious colour claims. State why the tempting alternative is too strong, incomplete or about a different stage.

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3. Do not say the filter adds colour

The filter changes which parts of the incoming light continue. It does not create red light from darkness or convert every incoming colour into red.

Build the explanation by naming the colours present in the incident light and the filter’s selective transmission and absorption. A remembered keyword is not enough: connect the observation to the mechanism and identify what would have to change for the conclusion to change.

Repair the nearest misconception by checking the light reflected by the object after filtering and returning to source filter object observer order brightness controls and cautious colour claims. State why the tempting alternative is too strong, incomplete or about a different stage.

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4. Track source to filter to object to eye

The transmitted light reaches the object. The object can reflect only colours available in that illumination and compatible with its reflective properties. Some reflected light must then reach the eye.

Build the explanation by naming the colours present in the incident light and the filter’s selective transmission and absorption. A remembered keyword is not enough: connect the observation to the mechanism and identify what would have to change for the conclusion to change.

Repair the nearest misconception by checking the light reflected by the object after filtering and returning to source filter object observer order brightness controls and cautious colour claims. State why the tempting alternative is too strong, incomplete or about a different stage.

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5. Explain why objects can look dark

A blue object under red filtered light may reflect little light toward the eye because the available red light is largely absorbed by the object. Dark appearance is about low received light, not the object ceasing to exist.

Build the explanation by naming the colours present in the incident light and the filter’s selective transmission and absorption. A remembered keyword is not enough: connect the observation to the mechanism and identify what would have to change for the conclusion to change.

Repair the nearest misconception by checking the light reflected by the object after filtering and returning to source filter object observer order brightness controls and cautious colour claims. State why the tempting alternative is too strong, incomplete or about a different stage.

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6. Distinguish colour from brightness

Adding filters usually reduces total transmitted light. A colour may remain detectable while becoming dimmer, and apparent colour depends on source spectrum, filter and observer conditions.

Build the explanation by naming the colours present in the incident light and the filter’s selective transmission and absorption. A remembered keyword is not enough: connect the observation to the mechanism and identify what would have to change for the conclusion to change.

Repair the nearest misconception by checking the light reflected by the object after filtering and returning to source filter object observer order brightness controls and cautious colour claims. State why the tempting alternative is too strong, incomplete or about a different stage.

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7. Design a controlled comparison

Keep source, distance, object, room light and observer position fixed. Change one filter, record transmitted colour and brightness separately, and avoid judging from camera auto-adjustment alone.

Build the explanation by naming the colours present in the incident light and the filter’s selective transmission and absorption. A remembered keyword is not enough: connect the observation to the mechanism and identify what would have to change for the conclusion to change.

Repair the nearest misconception by checking the light reflected by the object after filtering and returning to source filter object observer order brightness controls and cautious colour claims. State why the tempting alternative is too strong, incomplete or about a different stage.

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8. Control the examination explanation

Name the incident colours, state what the filter transmits and absorbs, track what the object reflects to the eye, and limit the conclusion to the tested lighting conditions.

Build the explanation by naming the colours present in the incident light and the filter’s selective transmission and absorption. A remembered keyword is not enough: connect the observation to the mechanism and identify what would have to change for the conclusion to change.

Repair the nearest misconception by checking the light reflected by the object after filtering and returning to source filter object observer order brightness controls and cautious colour claims. State why the tempting alternative is too strong, incomplete or about a different stage.

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CHAPTER 9 OF 12 · Back to contents

9. Worked examples

Worked case 1: White light passes through an ideal red filter. What mainly emerges?

Controlled answer. Red light. The filter selectively transmits red and absorbs much of the rest.

Mechanism. Identify the exact relationship, apply the relevant rule and preserve every stated condition. A surface clue may be compatible with several explanations, so the answer must show what makes this case decisive.

Misconception repair. Do not turn partial evidence into complete proof. Name the closest wrong answer, identify its missing condition and explain why the observed evidence supports the narrower conclusion.

Transfer. Compare with a blue filter. Solve the altered case from the mechanism rather than copying the previous wording.

Reverse construction. Begin with the controlled answer “Red light” and invent a fresh prompt that would justify it for the same reason. Then change one decisive condition to create a near-nonexample. This reverse task checks whether the learner owns the boundary rather than merely recognising the original sentence.

Explanation standard. A complete explanation names the observation, connects it to the rule and limits the conclusion to what follows. It should remain valid if decorative details are removed. If the explanation depends on the story topic instead of the decisive relation, rebuild it.

Audit. Recheck the colours present in the incident light, the filter’s selective transmission and absorption, the light reflected by the object after filtering, source filter object observer order brightness controls and cautious colour claims. Decide whether the evidence proves the conclusion or only supports a limited statement.

Worked case 2: Blue light reaches an ideal red filter. What is expected?

Controlled answer. Very little light emerges. The input lacks red for the filter to transmit, while blue is mostly absorbed.

Mechanism. Identify the exact relationship, apply the relevant rule and preserve every stated condition. A surface clue may be compatible with several explanations, so the answer must show what makes this case decisive.

Misconception repair. Do not turn partial evidence into complete proof. Name the closest wrong answer, identify its missing condition and explain why the observed evidence supports the narrower conclusion.

Transfer. State why the filter does not create red. Solve the altered case from the mechanism rather than copying the previous wording.

Reverse construction. Begin with the controlled answer “Very little light emerges” and invent a fresh prompt that would justify it for the same reason. Then change one decisive condition to create a near-nonexample. This reverse task checks whether the learner owns the boundary rather than merely recognising the original sentence.

Explanation standard. A complete explanation names the observation, connects it to the rule and limits the conclusion to what follows. It should remain valid if decorative details are removed. If the explanation depends on the story topic instead of the decisive relation, rebuild it.

Audit. Recheck the colours present in the incident light, the filter’s selective transmission and absorption, the light reflected by the object after filtering, source filter object observer order brightness controls and cautious colour claims. Decide whether the evidence proves the conclusion or only supports a limited statement.

Worked case 3: Why does a red filter look red in white light?

Controlled answer. Red light is transmitted or reflected toward the eye more strongly than many other colours. Appearance depends on received light.

Mechanism. Identify the exact relationship, apply the relevant rule and preserve every stated condition. A surface clue may be compatible with several explanations, so the answer must show what makes this case decisive.

Misconception repair. Do not turn partial evidence into complete proof. Name the closest wrong answer, identify its missing condition and explain why the observed evidence supports the narrower conclusion.

Transfer. Test under a red source. Solve the altered case from the mechanism rather than copying the previous wording.

Reverse construction. Begin with the controlled answer “Red light is transmitted or reflected toward the eye more strongly than many other colours” and invent a fresh prompt that would justify it for the same reason. Then change one decisive condition to create a near-nonexample. This reverse task checks whether the learner owns the boundary rather than merely recognising the original sentence.

Explanation standard. A complete explanation names the observation, connects it to the rule and limits the conclusion to what follows. It should remain valid if decorative details are removed. If the explanation depends on the story topic instead of the decisive relation, rebuild it.

Audit. Recheck the colours present in the incident light, the filter’s selective transmission and absorption, the light reflected by the object after filtering, source filter object observer order brightness controls and cautious colour claims. Decide whether the evidence proves the conclusion or only supports a limited statement.

Worked case 4: Repair: a red filter changes blue light into red light.

Controlled answer. A red filter mostly absorbs blue light and cannot create red light from it. Selective transmission is not colour conversion.

Mechanism. Identify the exact relationship, apply the relevant rule and preserve every stated condition. A surface clue may be compatible with several explanations, so the answer must show what makes this case decisive.

Misconception repair. Do not turn partial evidence into complete proof. Name the closest wrong answer, identify its missing condition and explain why the observed evidence supports the narrower conclusion.

Transfer. Draw the input-output path. Solve the altered case from the mechanism rather than copying the previous wording.

Reverse construction. Begin with the controlled answer “A red filter mostly absorbs blue light and cannot create red light from it” and invent a fresh prompt that would justify it for the same reason. Then change one decisive condition to create a near-nonexample. This reverse task checks whether the learner owns the boundary rather than merely recognising the original sentence.

Explanation standard. A complete explanation names the observation, connects it to the rule and limits the conclusion to what follows. It should remain valid if decorative details are removed. If the explanation depends on the story topic instead of the decisive relation, rebuild it.

Audit. Recheck the colours present in the incident light, the filter’s selective transmission and absorption, the light reflected by the object after filtering, source filter object observer order brightness controls and cautious colour claims. Decide whether the evidence proves the conclusion or only supports a limited statement.

Worked case 5: A red apple is viewed through a red filter under white light. What may happen?

Controlled answer. It may still appear red but dimmer. Red light reflected by the apple can pass through the filter, while total light is reduced.

Mechanism. Identify the exact relationship, apply the relevant rule and preserve every stated condition. A surface clue may be compatible with several explanations, so the answer must show what makes this case decisive.

Misconception repair. Do not turn partial evidence into complete proof. Name the closest wrong answer, identify its missing condition and explain why the observed evidence supports the narrower conclusion.

Transfer. Keep surface and source fixed. Solve the altered case from the mechanism rather than copying the previous wording.

Reverse construction. Begin with the controlled answer “It may still appear red but dimmer” and invent a fresh prompt that would justify it for the same reason. Then change one decisive condition to create a near-nonexample. This reverse task checks whether the learner owns the boundary rather than merely recognising the original sentence.

Explanation standard. A complete explanation names the observation, connects it to the rule and limits the conclusion to what follows. It should remain valid if decorative details are removed. If the explanation depends on the story topic instead of the decisive relation, rebuild it.

Audit. Recheck the colours present in the incident light, the filter’s selective transmission and absorption, the light reflected by the object after filtering, source filter object observer order brightness controls and cautious colour claims. Decide whether the evidence proves the conclusion or only supports a limited statement.

Worked case 6: A blue object is viewed under red light. Why may it look dark?

Controlled answer. It reflects little of the available red light toward the eye. The usual blue-reflecting appearance requires blue illumination.

Mechanism. Identify the exact relationship, apply the relevant rule and preserve every stated condition. A surface clue may be compatible with several explanations, so the answer must show what makes this case decisive.

Misconception repair. Do not turn partial evidence into complete proof. Name the closest wrong answer, identify its missing condition and explain why the observed evidence supports the narrower conclusion.

Transfer. Restore white light. Solve the altered case from the mechanism rather than copying the previous wording.

Reverse construction. Begin with the controlled answer “It reflects little of the available red light toward the eye” and invent a fresh prompt that would justify it for the same reason. Then change one decisive condition to create a near-nonexample. This reverse task checks whether the learner owns the boundary rather than merely recognising the original sentence.

Explanation standard. A complete explanation names the observation, connects it to the rule and limits the conclusion to what follows. It should remain valid if decorative details are removed. If the explanation depends on the story topic instead of the decisive relation, rebuild it.

Audit. Recheck the colours present in the incident light, the filter’s selective transmission and absorption, the light reflected by the object after filtering, source filter object observer order brightness controls and cautious colour claims. Decide whether the evidence proves the conclusion or only supports a limited statement.

Worked case 7: Can a filter transmit light in complete darkness?

Controlled answer. No. There is no incident light to transmit.

Mechanism. Identify the exact relationship, apply the relevant rule and preserve every stated condition. A surface clue may be compatible with several explanations, so the answer must show what makes this case decisive.

Misconception repair. Do not turn partial evidence into complete proof. Name the closest wrong answer, identify its missing condition and explain why the observed evidence supports the narrower conclusion.

Transfer. Separate material property from source condition. Solve the altered case from the mechanism rather than copying the previous wording.

Reverse construction. Begin with the controlled answer “No” and invent a fresh prompt that would justify it for the same reason. Then change one decisive condition to create a near-nonexample. This reverse task checks whether the learner owns the boundary rather than merely recognising the original sentence.

Explanation standard. A complete explanation names the observation, connects it to the rule and limits the conclusion to what follows. It should remain valid if decorative details are removed. If the explanation depends on the story topic instead of the decisive relation, rebuild it.

Audit. Recheck the colours present in the incident light, the filter’s selective transmission and absorption, the light reflected by the object after filtering, source filter object observer order brightness controls and cautious colour claims. Decide whether the evidence proves the conclusion or only supports a limited statement.

Worked case 8: What order should a ray account follow?

Controlled answer. Source, filter, object if present, then eye. Each stage constrains the next.

Mechanism. Identify the exact relationship, apply the relevant rule and preserve every stated condition. A surface clue may be compatible with several explanations, so the answer must show what makes this case decisive.

Misconception repair. Do not turn partial evidence into complete proof. Name the closest wrong answer, identify its missing condition and explain why the observed evidence supports the narrower conclusion.

Transfer. Reverse-trace only as a checking tool. Solve the altered case from the mechanism rather than copying the previous wording.

Reverse construction. Begin with the controlled answer “Source, filter, object if present, then eye” and invent a fresh prompt that would justify it for the same reason. Then change one decisive condition to create a near-nonexample. This reverse task checks whether the learner owns the boundary rather than merely recognising the original sentence.

Explanation standard. A complete explanation names the observation, connects it to the rule and limits the conclusion to what follows. It should remain valid if decorative details are removed. If the explanation depends on the story topic instead of the decisive relation, rebuild it.

Audit. Recheck the colours present in the incident light, the filter’s selective transmission and absorption, the light reflected by the object after filtering, source filter object observer order brightness controls and cautious colour claims. Decide whether the evidence proves the conclusion or only supports a limited statement.

Worked case 9: Do two stacked filters usually make the view brighter?

Controlled answer. No. Each can absorb part of the remaining light, reducing transmission.

Mechanism. Identify the exact relationship, apply the relevant rule and preserve every stated condition. A surface clue may be compatible with several explanations, so the answer must show what makes this case decisive.

Misconception repair. Do not turn partial evidence into complete proof. Name the closest wrong answer, identify its missing condition and explain why the observed evidence supports the narrower conclusion.

Transfer. Control for filter order and cleanliness. Solve the altered case from the mechanism rather than copying the previous wording.

Reverse construction. Begin with the controlled answer “No” and invent a fresh prompt that would justify it for the same reason. Then change one decisive condition to create a near-nonexample. This reverse task checks whether the learner owns the boundary rather than merely recognising the original sentence.

Explanation standard. A complete explanation names the observation, connects it to the rule and limits the conclusion to what follows. It should remain valid if decorative details are removed. If the explanation depends on the story topic instead of the decisive relation, rebuild it.

Audit. Recheck the colours present in the incident light, the filter’s selective transmission and absorption, the light reflected by the object after filtering, source filter object observer order brightness controls and cautious colour claims. Decide whether the evidence proves the conclusion or only supports a limited statement.

Worked case 10: An ideal red filter and ideal blue filter are stacked. What simplified prediction follows?

Controlled answer. Very little light passes. Their strong transmission bands do not overlap in the simplified model.

Mechanism. Identify the exact relationship, apply the relevant rule and preserve every stated condition. A surface clue may be compatible with several explanations, so the answer must show what makes this case decisive.

Misconception repair. Do not turn partial evidence into complete proof. Name the closest wrong answer, identify its missing condition and explain why the observed evidence supports the narrower conclusion.

Transfer. Mention real-filter leakage cautiously. Solve the altered case from the mechanism rather than copying the previous wording.

Reverse construction. Begin with the controlled answer “Very little light passes” and invent a fresh prompt that would justify it for the same reason. Then change one decisive condition to create a near-nonexample. This reverse task checks whether the learner owns the boundary rather than merely recognising the original sentence.

Explanation standard. A complete explanation names the observation, connects it to the rule and limits the conclusion to what follows. It should remain valid if decorative details are removed. If the explanation depends on the story topic instead of the decisive relation, rebuild it.

Audit. Recheck the colours present in the incident light, the filter’s selective transmission and absorption, the light reflected by the object after filtering, source filter object observer order brightness controls and cautious colour claims. Decide whether the evidence proves the conclusion or only supports a limited statement.

Worked case 11: Does a white object remain bright under every coloured filter?

Controlled answer. Not equally bright. It can reflect available transmitted light, but the filter reduces and selects the illumination.

Mechanism. Identify the exact relationship, apply the relevant rule and preserve every stated condition. A surface clue may be compatible with several explanations, so the answer must show what makes this case decisive.

Misconception repair. Do not turn partial evidence into complete proof. Name the closest wrong answer, identify its missing condition and explain why the observed evidence supports the narrower conclusion.

Transfer. Compare brightness and hue. Solve the altered case from the mechanism rather than copying the previous wording.

Reverse construction. Begin with the controlled answer “Not equally bright” and invent a fresh prompt that would justify it for the same reason. Then change one decisive condition to create a near-nonexample. This reverse task checks whether the learner owns the boundary rather than merely recognising the original sentence.

Explanation standard. A complete explanation names the observation, connects it to the rule and limits the conclusion to what follows. It should remain valid if decorative details are removed. If the explanation depends on the story topic instead of the decisive relation, rebuild it.

Audit. Recheck the colours present in the incident light, the filter’s selective transmission and absorption, the light reflected by the object after filtering, source filter object observer order brightness controls and cautious colour claims. Decide whether the evidence proves the conclusion or only supports a limited statement.

Worked case 12: Why might a phone photograph mislead the comparison?

Controlled answer. Automatic exposure and white balance can alter recorded brightness and colour. The camera is another measurement system.

Mechanism. Identify the exact relationship, apply the relevant rule and preserve every stated condition. A surface clue may be compatible with several explanations, so the answer must show what makes this case decisive.

Misconception repair. Do not turn partial evidence into complete proof. Name the closest wrong answer, identify its missing condition and explain why the observed evidence supports the narrower conclusion.

Transfer. Lock settings or use direct measurements. Solve the altered case from the mechanism rather than copying the previous wording.

Reverse construction. Begin with the controlled answer “Automatic exposure and white balance can alter recorded brightness and colour” and invent a fresh prompt that would justify it for the same reason. Then change one decisive condition to create a near-nonexample. This reverse task checks whether the learner owns the boundary rather than merely recognising the original sentence.

Explanation standard. A complete explanation names the observation, connects it to the rule and limits the conclusion to what follows. It should remain valid if decorative details are removed. If the explanation depends on the story topic instead of the decisive relation, rebuild it.

Audit. Recheck the colours present in the incident light, the filter’s selective transmission and absorption, the light reflected by the object after filtering, source filter object observer order brightness controls and cautious colour claims. Decide whether the evidence proves the conclusion or only supports a limited statement.

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CHAPTER 10 OF 12 · Back to contents

10. Independent practice

Practice 1: Which variable should change in a fair filter test?

Explained answer. The filter. Source, distance, object, angle and ambient light should be controlled.

Delayed transfer. List the controls. Cover the answer later and rebuild the chain.

Control question. Which exact condition does the nearest wrong answer miss? State it before checking.

Extension. Change one decisive feature while keeping the story similar. Explain why the conclusion now stays or changes.

Independent proof. Restate the answer without copying its wording. Your version must identify the evidence, the governing relationship and the boundary of the claim. Then write one fact that would be relevant but still insufficient on its own. This separates explanation from repetition.

Delayed comparison. Save this item beside the near-nonexample you created. On the next attempt, compare them before answering and point to the single feature that controls the difference. If more than one feature changed, revise the pair so the comparison stays fair.

Practice 2: What evidence shows selective transmission?

Explained answer. Different incident colours produce different transmitted intensities through the same filter. The result depends on wavelength or colour.

Delayed transfer. Use comparable source intensity. Cover the answer later and rebuild the chain.

Control question. Which exact condition does the nearest wrong answer miss? State it before checking.

Extension. Change one decisive feature while keeping the story similar. Explain why the conclusion now stays or changes.

Independent proof. Restate the answer without copying its wording. Your version must identify the evidence, the governing relationship and the boundary of the claim. Then write one fact that would be relevant but still insufficient on its own. This separates explanation from repetition.

Delayed comparison. Save this item beside the near-nonexample you created. On the next attempt, compare them before answering and point to the single feature that controls the difference. If more than one feature changed, revise the pair so the comparison stays fair.

Practice 3: Does absorbed light simply vanish?

Explained answer. Its energy is transferred to the material, often becoming thermal energy. The visible light is no longer transmitted.

Delayed transfer. Avoid claiming complete absorption without measurement. Cover the answer later and rebuild the chain.

Control question. Which exact condition does the nearest wrong answer miss? State it before checking.

Extension. Change one decisive feature while keeping the story similar. Explain why the conclusion now stays or changes.

Independent proof. Restate the answer without copying its wording. Your version must identify the evidence, the governing relationship and the boundary of the claim. Then write one fact that would be relevant but still insufficient on its own. This separates explanation from repetition.

Delayed comparison. Save this item beside the near-nonexample you created. On the next attempt, compare them before answering and point to the single feature that controls the difference. If more than one feature changed, revise the pair so the comparison stays fair.

Practice 4: Can a red object reflect blue strongly just because a blue filter is used?

Explained answer. Not necessarily. The object’s reflection properties and available illumination still control the result.

Delayed transfer. Track each stage. Cover the answer later and rebuild the chain.

Control question. Which exact condition does the nearest wrong answer miss? State it before checking.

Extension. Change one decisive feature while keeping the story similar. Explain why the conclusion now stays or changes.

Independent proof. Restate the answer without copying its wording. Your version must identify the evidence, the governing relationship and the boundary of the claim. Then write one fact that would be relevant but still insufficient on its own. This separates explanation from repetition.

Delayed comparison. Save this item beside the near-nonexample you created. On the next attempt, compare them before answering and point to the single feature that controls the difference. If more than one feature changed, revise the pair so the comparison stays fair.

Practice 5: What is the nearest wrong shortcut?

Explained answer. Naming the filter colour as the final answer without checking the incident light and object. The whole optical path determines observed light.

Delayed transfer. Use a missing-colour case. Cover the answer later and rebuild the chain.

Control question. Which exact condition does the nearest wrong answer miss? State it before checking.

Extension. Change one decisive feature while keeping the story similar. Explain why the conclusion now stays or changes.

Independent proof. Restate the answer without copying its wording. Your version must identify the evidence, the governing relationship and the boundary of the claim. Then write one fact that would be relevant but still insufficient on its own. This separates explanation from repetition.

Delayed comparison. Save this item beside the near-nonexample you created. On the next attempt, compare them before answering and point to the single feature that controls the difference. If more than one feature changed, revise the pair so the comparison stays fair.

Practice 6: Why record brightness separately from colour?

Explained answer. A filter can preserve a dominant hue while greatly reducing total light. Two observations answer different questions.

Delayed transfer. Create a two-column table. Cover the answer later and rebuild the chain.

Control question. Which exact condition does the nearest wrong answer miss? State it before checking.

Extension. Change one decisive feature while keeping the story similar. Explain why the conclusion now stays or changes.

Independent proof. Restate the answer without copying its wording. Your version must identify the evidence, the governing relationship and the boundary of the claim. Then write one fact that would be relevant but still insufficient on its own. This separates explanation from repetition.

Delayed comparison. Save this item beside the near-nonexample you created. On the next attempt, compare them before answering and point to the single feature that controls the difference. If more than one feature changed, revise the pair so the comparison stays fair.

Practice 7: What safety rule applies?

Explained answer. Do not look at the Sun or intense lamps through classroom filters. A coloured filter is not automatically safe eye protection.

Delayed transfer. Use low-intensity classroom sources. Cover the answer later and rebuild the chain.

Control question. Which exact condition does the nearest wrong answer miss? State it before checking.

Extension. Change one decisive feature while keeping the story similar. Explain why the conclusion now stays or changes.

Independent proof. Restate the answer without copying its wording. Your version must identify the evidence, the governing relationship and the boundary of the claim. Then write one fact that would be relevant but still insufficient on its own. This separates explanation from repetition.

Delayed comparison. Save this item beside the near-nonexample you created. On the next attempt, compare them before answering and point to the single feature that controls the difference. If more than one feature changed, revise the pair so the comparison stays fair.

Practice 8: State the full method.

Explained answer. Identify incident colours, apply selective transmission and absorption, track object reflection and light reaching the eye, compare brightness separately, control the setup and state the model’s limits. Do not describe filters as adding colour.

Delayed transfer. Test a new source-filter-object combination. Cover the answer later and rebuild the chain.

Control question. Which exact condition does the nearest wrong answer miss? State it before checking.

Extension. Change one decisive feature while keeping the story similar. Explain why the conclusion now stays or changes.

Independent proof. Restate the answer without copying its wording. Your version must identify the evidence, the governing relationship and the boundary of the claim. Then write one fact that would be relevant but still insufficient on its own. This separates explanation from repetition.

Delayed comparison. Save this item beside the near-nonexample you created. On the next attempt, compare them before answering and point to the single feature that controls the difference. If more than one feature changed, revise the pair so the comparison stays fair.

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CHAPTER 11 OF 12 · Back to contents

11. Delayed transfer

On day one, solve clear examples. On day three, mix examples, near-nonexamples and incomplete evidence. On day seven, solve without headings or a word bank. Delay reveals whether the method can be reconstructed independently.

Keep an error log for the first failed stage: reading, representation, rule, execution or checking. The earliest failure identifies the repair.

Interleave this skill with neighbouring ideas that share vocabulary. Classify each item only after naming the distinguishing condition.

In timed work, mark the relationship, apply the rule, write the conclusion and audit one condition. If checking changes the answer, record the overlooked feature.

Create a teach-back card with a near-nonexample on the front and the repaired mechanism on the back. Explain why the tempting answer fails.

Finish with one basic example, one boundary case and one transfer case. Supply explanations that a classmate can verify.

For a second delayed test, reverse the direction: start from a conclusion and invent evidence that would justify it, then evidence that would be insufficient. This exposes the boundary between relevance and proof.

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CHAPTER 12 OF 12 · Back to contents

12. Family guidance and FAQs

Guidance for parents and tutors

Ask for the decisive condition before confirming the answer. Use prompts such as “What exactly happened?”, “Which stage or meaning is this?” and “What would prove it?”

Fade support from labelled examples to mixed questions and delayed open response. Independent retrieval after time and topic change is the target.

Praise precise claim control. Narrowing an answer when evidence is incomplete is scientific and academic strength.

Frequently asked questions

Should I memorise the rule?

Memorise the compact rule, then practise examples and near-nonexamples so the conditions remain visible.

What if two answers seem possible?

Return to the exact relationship and choose the option satisfying every stated condition without adding facts.

Why delay practice?

Immediate repetition may depend on the recent explanation; delay tests reconstruction.

How should an error be corrected?

Name the first failed stage and practise it with a changed example.

When is the skill ready?

When the learner can explain, apply and transfer it after a delay.

What is the final audit?

Check relationship, mechanism, claim strength and whole-question fit.

Next routes

Continue at the Science learning hub or return to the series directory.

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