Question 1

Justin approached a cat and it moved away once he got nearer to it as shown below. Based on the diagram, which characteristic of living things did the cat show? Living things ____.

Accepted Answer

D. respond to changes in its surrounding. The cat moved away when Justin approached it, showing that it detected the change in its surrounding (Justin getting nearer) and responded by moving away. This demonstrates the characteristic that living things respond to changes in their surroundings.

Question 2

Li Ming set up the following experiment to find out if mould needs water to grow on bread. Two slices of similar type of bread, M and N, were placed in an airtight container and left on a table for a week. Which of the following shows the correct observation and explanation after a week?

Accepted Answer

B. Amount of mould on Bread M compared to Bread N: Less; Reason: less moisture in the bread. Bread M is toasted bread, which has less moisture (water) because toasting evaporates water. Bread N is fresh bread with more moisture. Since mould needs water to grow, less mould will form on Bread M because it has less moisture.

Question 3

John wants to get a new pair of reading spectacles. He would like one that allows him to bend part X easily so that it is more comfortable when wearing the spectacles. The table below shows four materials and their properties. A tick (✓) shows that the material has the property. Based on the table above, which of the materials, A, B, C or D, are suitable to make the different parts of the spectacles?

Accepted Answer

D. Lens: D, Part X: C. The lens must allow most light to pass through (transparent). The lens options are A, B, C, D — only B and D allow most light to pass through. Part X must be flexible (to bend easily) — only B and C are flexible. Therefore, Lens = D (allows light to pass through) and Part X = C (flexible). This matches option D.

Question 4

The diagram below shows the human digestive system. Which of the above part(s) absorb(s) digested food?

Accepted Answer

A. C only. In the digestive system diagram, A is the mouth/oesophagus, B is the stomach, C is the small intestine, and D is the large intestine. Digested food is absorbed by the small intestine (C). The large intestine absorbs water, not digested food.

Question 5

Study the life cycle of Insect P shown below. Which of the following statements can be concluded based on the diagram of the life cycle shown above?

Accepted Answer

D. P has a three-stage life cycle.. The diagram shows three stages: egg, nymph (young that looks like adult), and adult (stick-insect-like figure). This is a three-stage life cycle (incomplete metamorphosis). We cannot conclude what it feeds on or where it lays eggs from the diagram alone.

Question 6

Which of the following shows the correct life cycle of a plant?

Accepted Answer

C. Seed → young plant → adult plant → seed. The correct life cycle of a plant starts from a seed, which germinates into a young plant (seedling), grows into an adult plant which produces seeds, and the cycle continues. Option C correctly shows seed → young plant → adult plant → seed.

Question 7

Michelle wanted to test the magnetic strength of four magnets, Q, R, S and T. She lowered each magnet into the container and recorded the number of identical iron pins attracted by each magnet. Which of the following statements is most likely to be correct?

Accepted Answer

D. Magnet R is a stronger magnet than Magnet T.. The number of iron pins attracted indicates magnetic strength. Q attracts 8 pins (strongest), R attracts 5 pins, T attracts 3 pins, S attracts 1 pin (weakest). Therefore Magnet R (5 pins) is stronger than Magnet T (3 pins), making statement D correct.

Question 8

A magnet was brought near a mixture of four different materials, W, X, Y and Z, all placed inside a container as shown below. The result was as shown in the table below: Materials not attracted to the magnet: W and X; Materials attracted to the magnet: Y and Z. Next, Ken mixed three of the four materials in the container and brought the magnet near them. He observed that one material was separated out as shown. Which of the following shows the correct material that could be separated from the following mixtures using a magnet?

Accepted Answer

D. Mixture: Z, W and X; Material separated out: Z. Only Y and Z are attracted to the magnet. For the magnet to separate one material out, the mixture must contain exactly one of Y or Z (the magnetic ones). Option A has Y but two non-magnetic (W, X) and Y would be separated — but it says W is separated, which is wrong. Option D has Z, W and X — Z is the only magnetic one, so Z gets separated. This is correct.

Question 9

Which of the following has no mass and does not occupy space?

Accepted Answer

C. Shadow. Matter has mass and occupies space. Air, oil and a feather are all matter (they have mass and occupy space). A shadow is not matter — it is an absence of light, so it has no mass and does not occupy space.

Question 10

Susan made ice of different shapes using the ice tray shown below. She filled the tray with water and then left it in the freezer. Why was Susan able to make ice of different shapes with the ice tray?

Accepted Answer

C. Water does not have a definite shape.. Water is a liquid and takes the shape of its container (liquids do not have a definite shape). When the water filled the differently-shaped moulds and was frozen, the ice retained the shape of the moulds. So the reason different shapes were obtained is that water does not have a definite shape.

Question 11

Study the experiment shown below. The amount of water, A, which is collected in the small beaker, tells us the ____ of the stone.

Accepted Answer

B. volume. When a stone is placed into a container full of water, it displaces an amount of water equal to its own volume. The displaced water collected in the small beaker therefore measures the volume of the stone (water displacement method).

Question 12

A glass flask of volume 300 cm³ is connected to a syringe filled with air. If additional 40 cm³ of air is pumped into the flask, what would be the final volume of air in the glass flask?

Accepted Answer

C. 300 cm³. The glass flask has a fixed volume of 300 cm³. Although extra air is pumped in, gases can be compressed but the container's volume cannot increase. Therefore the air will occupy the entire flask, which is 300 cm³.

Question 13

Study the chart below. Which of the following best represents E, F, G and H?

Accepted Answer

C. E: light, F: water, G: air, H: paper. E is 'not matter' — light is not matter. F is matter without a definite shape, that cannot be compressed — water (liquid). G is matter without a definite shape that can be compressed — air (gas). H is matter with a definite shape and definite volume — paper (solid). So E=light, F=water, G=air, H=paper.

Question 14

Study the diagrams below carefully. Which of the following correctly arranges the objects' masses from the smallest to the greatest?

Accepted Answer

D. S → R → Q → T. From the first balance: Q on left balances (S + R) on right — so Q = S + R, meaning Q > R and Q > S. From the second balance: R is heavier than S (R side down). From the third balance: T is heavier than Q (T side down). So S < R, R < Q (since Q = R + S, Q is heavier than R), and Q < T. Order from smallest to greatest: S → R → Q → T.

Question 15

Which of the following is/are sources of light? A Sun, B Moon, C Mirror, D Lit torch

Accepted Answer

B. A and D only. Sources of light produce their own light. The Sun produces its own light (yes). The Moon reflects sunlight — not a source. A mirror reflects light — not a source. A lit torch produces its own light (yes). So only A (Sun) and D (Lit torch).

Question 16

Study the diagram below. Which of the following explains how Ben is able to see the newspaper?

Accepted Answer

D. The newspaper reflects light from the lamp into Ben's eyes.. We see non-luminous objects (like newspapers) when light from a source bounces off them into our eyes. The lamp produces light that hits the newspaper, and the newspaper reflects this light into Ben's eyes, allowing him to see it.

Question 17

Jane wants to use a mirror to see a cup which was placed behind the wall. Which of the following diagrams shows the correct position of the mirror?

Accepted Answer

A. Mirror positioned horizontally above both the wall and the cup. To see around the wall, the mirror must be placed where light from the cup can bounce off the mirror and reach Jane's eyes without being blocked. A mirror placed horizontally above both the wall and the cup allows light from the cup to travel up to the mirror, reflect off it, and travel down to Jane's eye over the top of the wall.

Question 18

An experiment shown below was conducted to compare the amount of light that passes through four different materials, W, X, Y and Z. A light sensor was used to detect how much light passes through each material. The readings were recorded in the table below. Based on the table above, which of the materials, W, X, Y or Z, will cast the darkest shadow on a screen?

Accepted Answer

C. Material Y. The darkest shadow is cast by the material that blocks the most light (allows the least light through). Readings: none=5000, W=4800, X=2900, Y=110, Z=600. Y allows the least light through (110 units), so it blocks the most light and casts the darkest shadow.

Question 19

Bala cut out a circular hole from a thick piece of rectangular-shaped paper and rolled it into a cylinder as shown below. He then used a torch to shine on the cylinder to form some shadows on a wall. Which of the following shadows cannot be formed by the cylinder?

Accepted Answer

C. Black rectangle with a small white circular hole in the middle. When light shines on the cylinder: a solid rectangle shadow forms when light hits the cylinder side without the hole facing the light (A is possible). A rectangle with a notch forms when the hole is at the edge of the cylinder (B is possible). The outline-of-a-circle shadow can form when light shines through the cylinder ends or along its axis (D is possible). However, a rectangle with a hole in the middle (C) cannot form because the cylinder is curved — the hole cannot project a clean circular hole inside an otherwise solid rectangle without distortion.

Question 20

Three cardboard pieces, A, B and C are arranged in a straight line at a certain distance apart as shown below. The three cardboard pieces have the same height. The diagram below shows the shadow that is cast on the screen. What are the shapes of A, B and C?

Accepted Answer

C. A: rectangle outline, B: arrow, C: trapezium. The shadow shows an arrow in the middle visible, surrounded by a rectangular outline frame. The cardboard closest to the screen (C) creates the outermost shape that's visible — the trapezium silhouette as the largest outer shape. Cardboard A (closest to torch, farthest from screen) blocks light first — it forms the rectangle outline meaning its solid shape is contained within others (so it must be hollow rectangle so we see through it). B is in the middle — the arrow shape is in the middle of the shadow. C nearest the screen produces the trapezium that frames the outside. Thus A = rectangle outline (hollow), B = arrow (solid), C = trapezium (solid frame around).

P4 Science CA1 2021 — Tao Nan

Related papers