PAPER 3: ESSAY

Based on the diagrams in Questions:(a) make one suitable inference

(b) state one appropriate

hypothesis that could be investigated.

(c) describe how you would design an experiment to test your hypothesis In your explanation, state clearly the following :

(i) aim of the experiment (ii) variables in the experiment(iii) list of apparatus and

materials(iv) arrangement of the apparatus(v) the procedures of the

experiment, which includes the method of controlling the manipulated variable and the method of measuring the responding variable

(vi) the way you would tabulate the data

(vii) the way you would analyse the data

[12 marks]

FORCE AND MOTION

Question 1: Linear MotionDiagram 3.1 shows a cylinder that is rolling down a wooden plank from a small lorry.Diagram 3.2 shows the same cylinder that is rolling down the same wooden plank from a big lorry. It is noticed that the cylinder is rolling faster from the big lorry.

Question 2: InertiaThe diagram below shows a boy and her mother each sit on similar swings. If they are given a push, it is found that the mother will be more difficult to be moved.

Question 3: F = maDiagram 3.1 shows a car pulling a heavily packed trailer. The trailer is attached to the car with a locking mechanism. The car’s engine is exerting a constant force that causes the car and the trailer to accelerate together.Diagram 3.2 shows what happens when the locking mechanism fails and the trailer is dislodged. The car lurches forward with an increased acceleration on its own.

Diagram 3.1

Diagram 3.2

Question 4: F = maA boy pushes the boxes along a level walkway as shown in Diagram 3.1 The boy experiences that the boxes move slowly. When the boy removes one of the boxes as shown in Diagram 3.2, he experiences that the boxes move faster than before although the same force was applied

Question 5: F = maDiagram 3.1 shows a lorry and a motorcycle stopping at a traffic light when the light is red.Diagram 3.2 shows the distance covered by the motorcyclist and the lorry driver 10 seconds after the light turns green.

Diagram 3.1 Diagram 3.2

Question 6: F = maDiagram 3.1 shows Jason and Jimmy on a tendon bicycle with Jimmy alone pedaling. They found that the speed of the bicycle increases at a slow rate. Diagram 3.2 shows that when both Jason and Jimmy are pedaling, the speed of the bicycle increases at a higher rate.

Question 7: SpringDiagram 3 shows two catapults A and B made from same catapult rubber. Difference forces are applied on the catapults.

FORCE AND PRESSURE

Question 8: Liquid pressure Figure 3 shows the cross-section of a dam. The wall has to be thicker at the bottom of the dam.

Question 9: Liquid pressureDiagram 3.1 shows a man is in a leaking sampan. He noticed that the spurt coming from the hole at the bottom of the sampan is higher compared to the one from the side.

Question 10: Liquid pressureThe diagram 3.1 and 3.2 show a diver swimming in the sea and in fresh water. The diver experiences more discomfort to his body and ear in Diagram 3.2.

Question 11: Archimedes’ principleDiagram 3.1 shows a boy lifted up a rock in the sea water. Diagram 3.2 shows the boy lifted up the rock at the surface of the sea water. He feel much heavier than before.

Question 12: Archimedes’ principleA man who is fishing, pulled out a fish out of the water as shown in Diagram 3.1. It becomes more difficult to pull out the fish out of the water and the rod is getting bender in Diagram 3.2.

Question 13: Archimedes’ principleDiagram 3.1 shows the part a floating cargo ship that is above water when it is fully loaded with cargo. Diagram 3.2 shows the part of the ship when most of the cargo has been removed.

HEAT

Question 14: Heat & temperatureDiagram 3 shows two pails, R and S, with R containing more water than S. Both the pails are exposed to sunlight. After a few hours it was observed that the water in pail S is hotter than the water in pail R.

Question 15: Boyle’s LawThe figure above shows air being released by a diver. Observe the changes in theair bubbles as they rise towards the surface.

Question 16: Boyle’s LawDiagram 3 shows air bubbles formed by an air pump in an aquarium. The sizes of the air bubbles are smaller as they emerged from the air pump at the bottom of the aquarium. The sizes become bigger as they approached the surface of the water.

Question 17: Boyle’s LawDiagram 3.1 shows a student holds a balloon which is tied to a string. When she releases the balloon, the balloon moves upward. She noticed that the balloon becomes bigger as it moves higher as shown in Diagram 3.2.

Question 18: Boyle’s LawDiagram 3.1 shows an inverted beaker contains an air trapped is converted and immersed in the water. Diagram 3.2 shows the volume of air trapped in the beaker decreased when the beaker is pushed down in the water.

Question 19: Charles’ LawDiagram 1.1 shows a cake before being baked. Diagram 1.2 show cake after being baked.

Design an experiment to test the hypothesis using capillary tube and other suitable apparatus.

Question 20: Charles’ LawDiagram 3.1 shows a balloon during cool day. During hot day the balloon becomes bigger as shown in diagram 3.2.

LIGHT

Question 21: LensesDiagram 3.1shows an object in front of a bulb. The object is 10 cm from the convex lens. A screen is placed behind the lens and the distance is adjusted until a sharp image is formed on the screen. The distance between the object and the lens is then increased as shown by diagram 3.2. The image formed on the screen in diagram 3.2 is smaller than in diagram 3.1.

Diagram 3.1

Diagram 3.2

Question 22: LensesDiagram 3.1 shows a laboratory poster being observed through a convex lens. Diagram 3.2 shows the laboratory poster observed through the same convex lens when the poster is brought closer to the lens.

WAVES

Question 23: WavesDiagram 4.1 shows a cradle with a baby in it is oscillating vertically. Diagram 4.2 shows another identical cradle with a heavier baby in it is oscillating vertically. It is observed that the cradle with a heavier mass baby oscillates at a higher frequency.

Question 24: Refraction of waveIn the ocean, the water is often more calm. As the waves move towards the beach they become more distinct as shown by diagram 4.1. Study the shape and wave length shown in diagram 4.1.

Question 25: Refraction of waveWater is dripped at a constant rate into two different containers as shown in Diagram 4.The cross-section of the water waves formed from the droplets in thecontainers are shown in diagrams below.

Question 26 : Interference of waveA student who moves his ear near a vibrating tuning fork hears loud and soft sounds alternately.Diagram 4.1 shows the positions of loud sounds are closer together.Diagram 4.2 shows the positions of loud sound are further apart.

ELECTRICITY

Question 27: Ohm’s LawDiagram 4.1 shows a bulb which lights up when it is connected to one dry cell. Diagram 4.2 shows the condition of the same bulb when it is connected to two dry cells.

Question 28: A student is investigating the performance of a dc motor.Diagram 4.1 shows the final position of the load if the student connected the motor to a dry cell. Then the student connected the motor to two dry cell and the final position of theload lifted is shown in Diagram 4.2.Both of the experiments are started when the load is on the floor.

Question 29: ResistanceThe diagram 4.1 and 4.2 show two circuits with identical bulbs and dry cells. The wire connected to bulb in Diagram 4.1 is thicker than the wire connected to bulb in Diagram 4.2. Both the wires are of the same length. The bulb in Diagram 4.1 lightsup brighter than the bulb in Diagram 4.2.

Question 30: ResistanceDiagram 4.1 and 4.2 show Adnan selling fruits at two different night market. He finds that the bulb at his stall lights up brighter when he uses a shorter wire.

Diagram 4.1

Diagram 4.2

Question 31: ElectromagnetDiagram 4.1 shows an electromagnetic lifting machine used to lift scrap metal. Diagram 4.2 shows the observation of the machine when the current flows through the machine is increased.

Diagram 4.1 Diagram 4.2

Question 32: ElectromagnetDiagram 4.1 and Diagram 4.2 show an electric bell. In Diagram 4.1, when it is connected to two batteries, the bell will ring. In Diagram .2, when it is connected to four batteries, the bell will ring louder. When the bell ring louder, the force exerted on the hammer is greater.

Question 33: ElectromagnetDiagram 4 shows the telephone ear piece which receives a varying current from the telephone line. The permanent magnet attracts the magnet alloy diaphragm. The varying current in the coils of the electromagnet changes the strength of the magnetic field

Question 34: MotorDiagram 4.1 shows a model of direct current motor. A student investigate that affected the speed of the motor rotation

Question 35: Electromagnetic InductionFigure 4 shows a boy cycling at night. The bicycle’s lamp becomes brighter when he cycles faster.

Question 36: TransformerDiagram shows a step down transformer. A primary coil is connected to the input supply 240V a.c. Diagram 4.1(a) and diagram 4.1(b) shows a bulb that is connected to a secondary coil. It is observed that the brightness of the bulb in diagram 4.1(b) is brighter than in diagram 4.1(a).