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P3 General Studies: Light and Shadows (Paper 1 (basics))
Tutor Prep Guide · straight-line light, shadow direction and length, reflection angles and the normal, sundials and pinhole images
P3 General Studies: Light and Shadows (Paper 1 (basics))
Paper one starts from the single cause, that light travels straight, and practises shadow direction, shadow length and simple percentages.
Direct answers Ask first where the light comes from, then where the shadow falls; both answers must show opposite sides.
01 Paper details (check answers afterwards)
| Item | Detail |
|---|---|
| Questions | 10 |
| Suggested time | 20 |
| Difficulty mix | Foundation 3 · Intermediate 3 · Challenge 3 · Error redo 1 |
| Chapter | Chapter: P3 General Studies: Light and Shadows |
| Level | parts of a closed circuit, conductors against insulators, series against parallel, adding up battery voltage, and electrical safety |
02 Questions (10 items)
- FoundationDoes the Moon give out light itself? Is it a light source?
- FoundationAlong what path does light travel in air?
- FoundationWhen the Sun is in the east, on which side is a person shadow?
- IntermediateThree of four objects are opaque. What percentage are opaque?
- IntermediateIn 6 trials the shadow fell to the left 4 times. What percentage is that?
- IntermediateA 1 m tall object casts a 2 m shadow. How many times the height is the shadow?
- ChallengeWhen is a shadow shortest during the day?
- ChallengeA torch shines through a small hole in card and only one bright spot appears on the wall. What property of light does this show?
- ChallengeWhich lets light through, wood or glass?
- Error redoA classmate draws the midday shadow directly under the person. Is that right?
03 Answers and one-line notes
| # | Answer | One-line note |
|---|---|---|
| 1 | No. The Moon is not a light source; it reflects sunlight | A light source makes its own light, while the Moon only reflects sunlight. |
| 2 | It travels in straight lines | Light travels in straight lines, so nothing behind an opaque object is lit. |
| 3 | On the west side | A shadow always falls on the side opposite the light source, so an eastern Sun gives a western shadow. |
| 4 | 75.0 Percentage points | Three divided by four times one hundred gives 75.0 percentage points. |
| 5 | 66.7 Percentage points | Four divided by six times one hundred is 66.7 percentage points to one decimal place. |
| 6 | 2.0 times | Two divided by one equals 2.0. |
| 7 | At noon, when the Sun is highest | The higher the Sun, the closer the light is to vertical, so the shadow is shorter. |
| 8 | Light travels in straight lines | Only light travelling straight through the hole reaches the wall, so just one spot appears. |
| 9 | Glass does; wood does not | Glass is transparent and wood is opaque, so a shadow forms behind wood. |
| 10 | No. The shadow must be drawn on the opposite side to the light source | A shadow is where light is blocked, so it always lies opposite the light source. |
04 What to do after marking
- After marking, redo only the wrong items and write down which step went wrong (formula, unit, or misread number).
- Repeat the same item two days later; move to the next paper only when both attempts are correct.
- Parents only need the answer and note columns; there is no need to explain every item.
After paper one, take paper two and sort out series against parallel in one pass.Tutor Registration →
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