From Real Exams Quiz
Primary 6 PSLE Science Light Quiz
Free P6 PSLE Science Light quiz, Ox Exam version, with questions, answers, and PSLE-focused practice for Singapore students.
These static practice materials are generated from the site's syllabus and paper-generation workflow, with source and model context shown so students and parents can evaluate the material before use.
Questions
Free quiz and exam paper access
Enter your details to view this paper
Your access is remembered on this device.
Answers
Primary 6 PSLE Science Quiz - Light: Answer Key
Total Marks: 50
Section A: Multiple-Choice (Questions 1-5)
Answer 1.
(C) The Sun — [2 marks] Teaching note: A light source makes its own light. The Sun burns and gives out light naturally. The Moon and a mirror only reflect light from other sources; a street lamp gives out light but is man-made, not natural. Common mistake: choosing the Moon because it "glows" at night — it glows only because it reflects sunlight.
Answer 2.
(B) — [2 marks] When the Sun is almost directly overhead, its rays come down steeply, so the pole blocks only a small stretch of light on the ground and the shadow is shortest. Early and late in the day the Sun is low, and low rays stretch shadows out long.
Answer 3.
(D) Cardboard — [2 marks] Cardboard is opaque: it does not allow any light to pass, so it blocks all the torch light and casts the
<stage3_quiz_answers_md>
Primary 6 PSLE Science Quiz - Light: Answer Key
Total Marks: 50
Section A: Multiple-Choice (Questions 1-5)
Answer 1.
(C) The Sun — [2 marks] Teaching note: A light source makes its own light. The Sun gives out light naturally. The Moon and a mirror only reflect light; a street lamp gives out light but is man-made, not natural.
Answer 2.
(B) — [2 marks] When the Sun is almost directly overhead, its steep rays mean the pole blocks only a small stretch of ground light, so the shadow is shortest. Low morning/evening Sun stretches shadows long.
Answer 3.
(D) Cardboard — [2 marks] Cardboard is opaque: no light passes through, so it blocks all the torch light and casts the darkest shadow. Glass, plastic wrap and tracing paper let some light through.
Answer 4.
(C) — [2 marks] Light from the lamp bounces off the apple and enters Mei's eyes. We see non-luminous objects only when reflected light from them enters our eyes.
Answer 5.
(B) — [2 marks] The two mirrors are parallel, each tilted at 45° to the tube, so light turns 90° at each mirror.
Section B: Short Answer (Questions 6-15)
Answer 6.
A light source makes its own light (e.g. the Sun, a candle). A reflector does not make light; it only bounces back light from a source (e.g. a mirror, the Moon). [2 marks]
Answer 7.
Light travels in straight lines. Blocked light cannot bend around the object, so the shadow keeps a similar outline shape to the object. [2 marks]
Answer 8.
Frosted glass is translucent. It lets some light pass but scatters it, so people outside see only blurred patches of light, not clear shapes. [2 marks]
Answer 9.
The shadow becomes smaller. When the torch is farther away, the toy blocks a narrower cone of light rays, so a smaller shadow forms on the screen. [2 marks]
Answer 10.
At 12:00 pm the Sun was almost directly overhead (at its highest position), so the pole blocked the least light along the ground and the shadow was shortest. [2 marks]
Answer 11.
Angle of incidence (from normal) = 90° − 40° = 50°. Angle of reflection = angle of incidence = 50°. [2 marks]
Answer 12.
The Moon reflects sunlight. The reflected light from the Moon's surface travels in straight lines and enters our eyes, so we can see it even though it is not a light source. [2 marks]
Answer 13.
It supports the conclusion that light travels in straight lines. When all three holes line up with the flame and the eye, straight-line paths exist through them. Moving Card 2 breaks the alignment, and since light cannot bend, it cannot reach Aiman's eye. [2 marks]
Answer 14.
A circular (round) shadow. The ball is spherical, and since light travels in straight lines, the shadow's outline matches the shape of the ball blocking the light. [2 marks]
Answer 15.
The sheet is translucent, so it lets only part of the lamp's light through while scattering it. The light reaching customers is therefore softer and dimmer, with less glare. [2 marks]
Section C: Open-Ended Application (Questions 16-20)
Answer 16.
- Variable changed: distance between the torch and the card
- Variable measured: size of the shadow formed on the screen
- Variables kept the same (any TWO): the same square card; the distance between the card and the screen; the same torch/brightness [3 marks]
Answer 17.
Light from the tree enters the top opening of the periscope travelling horizontally and strikes the top mirror tilted at 45°. The mirror reflects the ray through 90° downwards, so it travels straight down the tube. It then strikes the bottom mirror, also at 45°, which reflects it through another 90° so it leaves horizontally into the observer's eye. Because the two mirrors are parallel, the light keeps a straight-line path inside the tube, allowing the person to see the tree over the high wall. [4 marks]
Answer 18.
(a) The shadow decreased from 200 cm to 35 cm (8:00 am to 12:00 pm), then increased again to 195 cm (12:00 pm to 4:00 pm). [1 mark]
(b) In the morning the Sun is low, so shadows are long. As the Sun climbs towards its highest point at noon, shadows shorten. In the afternoon the Sun sinks lower again, so shadows lengthen once more. [2 marks]
(c) Longer. By 6:00 pm the Sun is even lower in the sky than at 4:00 pm, so the shadow continues to lengthen. [1 mark]
Answer 19.
| Material | Shadow observed | Reason |
|---|---|---|
| Clear plastic sheet | Bright patch | Transparent — almost all the torch light passes straight through |
| Greaseproof paper | Faint shadow | Translucent — some light passes through but is scattered |
| Black cardboard | Dark shadow | Opaque — no light passes through, so all light is blocked |
Answer 20.
(a) 50° (angle of reflection equals angle of incidence). [1 mark]
(b) 50°. The ray leaves M1 at 50° to M1's normal. Since M1 and M2 are parallel, their normals are also parallel, so the ray meets M2's normal at the same angle of 50°. [2 marks]
(c) The outgoing ray is parallel to the original incoming ray (travelling in the same direction, only shifted sideways). Because the mirrors are parallel, the second reflection reverses the change in direction caused by the first, so the ray's overall direction is restored. [2 marks]