Question 1 (Subtopic: 1.1)
Which vector diagram correctly shows the force Z as the resultant of forces X and Y?
▶️Answer/Explanation
Answer: D
Explanation: The correct vector diagram shows force Z as the resultant of forces X and Y, which means Z should be the diagonal of the parallelogram formed by X and Y. Option D correctly represents this.
Question 2 (Subtopic: 1.2)
An object falls towards the surface of the Earth. The object is falling at its terminal velocity.
Which statement is correct?
A: There is air resistance and the acceleration of the object is negative.
B: There is air resistance and the acceleration of the object is zero.
C: There is no air resistance and the acceleration of the object is negative.
D: There is no air resistance and the acceleration of the object is zero.
▶️Answer/Explanation
Answer: B
Explanation: At terminal velocity, the force of air resistance equals the force of gravity, resulting in zero acceleration. Therefore, the correct statement is that there is air resistance and the acceleration of the object is zero.
Question 3 (Subtopic: 1.2)
The graph represents the motion of a vehicle.
What is the distance travelled by the vehicle in 400 s?
A: 20 m
B: 400 m
C: 4000 m
D: 8000 m
▶️Answer/Explanation
Answer: C
Explanation: The distance travelled can be calculated by finding the area under the speed-time graph. If the speed is constant at 20 m/s for 400 s, the distance is 20 m/s × 400 s = 8000 m. However, since the graph shows a linear increase, the average speed is 10 m/s, giving a distance of 10 m/s × 400 s = 4000 m.
Question 4 (Subtopic: 1.3)
On the Earth, a spring stretches by 5.0 cm when a mass of 3.0 kg is suspended from one end.
The gravitational field strength on the Moon is 1/6 of that on the Earth.
Which mass, on the Moon, would stretch the spring by the same extension?
A: 0.50 kg
B: 3.0 kg
C: 5.0 kg
D: 18 kg
▶️Answer/Explanation
Answer: D
Explanation: The gravitational field strength on the Moon is 1/6 of that on Earth. To achieve the same extension, the mass on the Moon must be 6 times the mass on Earth. Therefore, 3.0 kg × 6 = 18 kg.
Question 5 (Subtopic: 1.4)
A shopkeeper pours rice into a dish that hangs from a spring balance. He records the reading.
A customer buys some pasta. The shopkeeper notices that the reading on the spring balance, with just pasta in the dish, is the same as it was with just rice in the dish.
Which quantity must be the same for the rice and for the pasta?
A: density
B: temperature
C: volume
D: weight
▶️Answer/Explanation
Answer: D
Explanation: The spring balance measures weight. Since the reading is the same for both rice and pasta, their weights must be the same.
Question 6 (Subtopic: 1.4)
A student determines the density of an irregularly shaped stone. The stone is slowly lowered into a measuring cylinder partly filled with water.
Which other apparatus does the student need to calculate the density of the irregularly shaped stone?
A: a balance
B: a thermometer
C: a metre rule
D: a stop-watch
▶️Answer/Explanation
Answer: A
Explanation: To calculate density, the student needs to measure the mass of the stone using a balance and the volume using the displacement method in the measuring cylinder.
Question 7 (Subtopic: 1.5)
A train is travelling horizontally in a straight line. A book is on a table in the train. The diagram shows all the forces acting on the book.
How is the train moving?
A: accelerating to the left of the diagram
B: accelerating to the right of the diagram
C: moving at uniform speed to the left of the diagram
D: moving at uniform speed to the right of the diagram
▶️Answer/Explanation
Answer: B
Explanation: The forces acting on the book indicate that the train is accelerating to the right, as the frictional force acts in the opposite direction to the acceleration.
Question 8 (Subtopic: 1.5)
The diagrams show four beams, each of negligible weight and freely pivoted.
Which beam is not in equilibrium?
▶️Answer/Explanation
Answer: C
Explanation: For a beam to be in equilibrium, the moments about the pivot must balance. In option C, the moments do not balance, so the beam is not in equilibrium.
Question 9 (Subtopic: 1.5)
An object of mass 1.2 kg is moving with a velocity of 2.0 m/s when it is acted on by a force of 4.0 N. The velocity of the object increases to 5.0 m/s in the same direction. For which period of time does the force act on the object?
A: 0.90 s
B: 1.1 s
C: 1.5 s
D: 3.6 s
▶️Answer/Explanation
Answer: A
Explanation: Using the equation \( F = ma \), we can find the acceleration \( a = F/m = 4.0 \, \text{N} / 1.2 \, \text{kg} = 3.33 \, \text{m/s}^2 \). The change in velocity is \( 5.0 \, \text{m/s} – 2.0 \, \text{m/s} = 3.0 \, \text{m/s} \). The time taken is \( t = \Delta v / a = 3.0 \, \text{m/s} / 3.33 \, \text{m/s}^2 = 0.90 \, \text{s} \).
Question 10 (Subtopic: 1.7)
Which row about the change of energy in the energy store must be correct?
▶️Answer/Explanation
Answer: A
Explanation: When water is pumped up to a high-altitude dam, its gravitational potential energy increases due to the increase in height.
Question 11 (Subtopic: 1.7)
A woman of mass 50 kg has 81 J of kinetic energy.
What is her speed?
A: 1.3 m/s
B: 1.6 m/s
C: 1.8 m/s
D: 3.2 m/s
▶️Answer/Explanation
Answer: C
Explanation: The kinetic energy formula is \( KE = \frac{1}{2}mv^2 \). Rearranging for speed, \( v = \sqrt{\frac{2 \times KE}{m}} = \sqrt{\frac{2 \times 81}{50}} = \sqrt{3.24} = 1.8 \, \text{m/s} \).
Question 12 (Subtopic: 1.7)
A child runs up a set of stairs four times. The time taken for each run is recorded.
Which time is measured when the child’s useful power is greatest?
A: 10 s
B: 20 s
C: 30 s
D: 40 s
▶️Answer/Explanation
Answer: A
Explanation: Power is the rate of doing work, so the shorter the time taken to do the same amount of work, the greater the power. Therefore, the child’s useful power is greatest when the time taken is the shortest, which is 10 s.
Question 13 (Subtopic: 1.8)
A dam holds water in a reservoir. The height of the water in the reservoir is 15 m.
The density of water is 1000 kg/m\(^3\).
What is the pressure due to the water at the bottom of the dam?
A: 6.8 Pa
B: 1500 Pa
C: 15000 Pa
D: 150000 Pa
▶️Answer/Explanation
Answer: D
Explanation: The pressure due to a column of liquid is given by \( P = \rho g h \), where \( \rho \) is the density, \( g \) is the acceleration due to gravity (9.8 m/s\(^2\)), and \( h \) is the height. Substituting the values, \( P = 1000 \times 9.8 \times 15 = 147000 \, \text{Pa} \), which is approximately 150000 Pa.
Question 14 (Subtopic: 2.1)
A student uses a microscope to observe pollen moving on the surface of water. Which statement describes the reason for this movement?
A: Water molecules are moved by microscopic pollen particles.
B: Water molecules are moved by pollen molecules.
C: Microscopic pollen particles are moved by water molecules.
D: Pollen molecules are moved by water molecules.
▶️Answer/Explanation
Answer: C
Explanation: The movement of pollen particles on the surface of water is due to the random motion of water molecules, which is evidence of the kinetic particle model of matter. The water molecules collide with the pollen particles, causing them to move.
Question 15 (Subtopic: 2.2)
Which statements about evaporation of water are correct?
1: Evaporation causes the remaining liquid to cool.
2: During evaporation, the more energetic particles escape from the surface of the liquid.
3: Evaporation only happens at 100 °C.
A: 1, 2 and 3
B: 1 and 2 only
C: 1 and 3 only
D: 2 and 3 only
▶️Answer/Explanation
Answer: B
Explanation: Evaporation causes the remaining liquid to cool because the more energetic particles escape from the surface, taking away energy. Evaporation can occur at any temperature, not just at 100 °C, so statement 3 is incorrect.
Question 16 (Subtopic: 2.3)
Some hot water is sealed inside a metal can. The can is in a vacuum in outer space. The hot water slowly cools down. How does the thermal energy escape into space?
A: by conduction then convection
B: by conduction then radiation
C: by evaporation then convection
D: by evaporation then radiation
▶️Answer/Explanation
Answer: B
Explanation: In a vacuum, convection cannot occur because there is no medium for the heat to transfer through. The thermal energy escapes by conduction through the metal can and then by radiation into space.
Question 17 (Subtopic: 3.1)
The diagrams show graphs of displacement against time for four waves. All the graphs are drawn to the same scale. Which wave has the largest amplitude and the highest frequency?
▶️Answer/Explanation
Answer: A
Explanation: The wave with the largest amplitude and the highest frequency will have the tallest peaks and the most waves in a given time period. Option A shows this characteristic.
Question 18 (Subtopic: 3.2)
The diagram shows a ray of light entering a glass block.
Which calculation gives the refractive index of the glass?
A: \(\frac{\sin 40^\circ}{\sin 25^\circ}\)
B: \(\frac{\sin 40^\circ}{\sin 65^\circ}\)
C: \(\frac{\sin 50^\circ}{\sin 25^\circ}\)
D: \(\frac{\sin 50^\circ}{\sin 65^\circ}\)
▶️Answer/Explanation
Answer: A
Question 19 (Subtopic: 3.2)
An object O is placed at point P near to a thin converging lens. The diagram shows three rays from the top of O passing through the lens. Each point F is one focal length from the centre of the lens. Each point 2F is two focal lengths from the centre of the lens.
The object O is moved to point Q on the diagram.
Which type of image is produced when the object O is at point Q?
A: inverted and the same size as the object
B: inverted and enlarged
C: upright and the same size as the object
D: upright and enlarged
▶️Answer/Explanation
Answer: B
Explanation: When the object is placed between the focal point (F) and twice the focal length (2F) of a converging lens, the image formed is inverted and enlarged.
Question 20 (Subtopic: 3.2)
Which diagram shows the dispersion of white light by a glass prism?
▶️Answer/Explanation
Answer: B
Explanation: Dispersion of white light by a glass prism results in the separation of light into its constituent colors (red, orange, yellow, green, blue, indigo, violet). Option A correctly shows this separation.
Question 21 (Subtopic: 3.3)
Visible light has wavelengths in the range \( 4.0 \times 10^{-7} \, \text{m} \) to \( 7.0 \times 10^{-7} \, \text{m} \). What is the range of the frequencies of visible light?
A: 0.12 Hz to 0.21 Hz
B: 120 Hz to 210 Hz
C: \( 4.3 \times 10^{11} \, \text{Hz} \) to \( 7.5 \times 10^{11} \, \text{Hz} \)
D: \( 4.3 \times 10^{14} \, \text{Hz} \) to \( 7.5 \times 10^{14} \, \text{Hz} \)
▶️Answer/Explanation
Answer: D
Explanation: The frequency \( f \) of light is related to its wavelength \( \lambda \) by the equation \( f = \frac{c}{\lambda} \), where \( c \) is the speed of light (\( 3.0 \times 10^8 \, \text{m/s} \)). For \( \lambda = 4.0 \times 10^{-7} \, \text{m} \), \( f = \frac{3.0 \times 10^8}{4.0 \times 10^{-7}} = 7.5 \times 10^{14} \, \text{Hz} \). For \( \lambda = 7.0 \times 10^{-7} \, \text{m} \), \( f = \frac{3.0 \times 10^8}{7.0 \times 10^{-7}} = 4.3 \times 10^{14} \, \text{Hz} \). Therefore, the range of frequencies is \( 4.3 \times 10^{14} \, \text{Hz} \) to \( 7.5 \times 10^{14} \, \text{Hz} \).
Question 22 (Subtopic: 3.4)
Student X fires a starting pistol which produces smoke and sound. Student Y is standing 100 m away and sees the smoke the instant it is produced. The speed of sound in air is 340 m/s. What is the time delay between student Y seeing the smoke and hearing the sound?
A: 0.29 s
B: 0.59 s
C: 1.7 s
D: 3.4 s
▶️Answer/Explanation
Answer: A
Explanation: The time delay is the time it takes for sound to travel 100 m. Using the equation \( t = \frac{d}{v} \), where \( d = 100 \, \text{m} \) and \( v = 340 \, \text{m/s} \), we get \( t = \frac{100}{340} = 0.29 \, \text{s} \).
Question 23 (Subtopic: 4.1)
An unmagnetised piece of soft iron is placed close to a strong permanent magnet, as shown.
What is the induced polarity of end X of the soft iron and in which direction does the magnetic force act on the soft iron?
▶️Answer/Explanation
Answer: C
Explanation: When a piece of soft iron is placed near a permanent magnet, it becomes magnetized by induction. The end closest to the magnet’s north pole becomes a south pole (S), and the force acts towards the magnet, which is to the left in this case.
Question 24 (Subtopic: 4.2)
A plastic rod is rubbed with a cloth.
The rod and the cloth both become charged as electrons move between them. The rod becomes negatively charged.
Which diagram shows how the rod becomes negatively charged and shows the final charge on the cloth?
▶️Answer/Explanation
Answer: B
Explanation: When the plastic rod is rubbed with the cloth, electrons are transferred from the cloth to the rod, making the rod negatively charged and the cloth positively charged. Option B correctly shows this transfer of electrons and the resulting charges.
Question 25 (Subtopic: 4.2)
A wire has a uniform circular cross-sectional area. Which statement is correct?
A: The resistance of the wire is directly proportional to its cross-sectional area and inversely proportional to its diameter.
B: The resistance of the wire is directly proportional to its cross-sectional area and inversely proportional to its length.
C: The resistance of the wire is directly proportional to its length and inversely proportional to its cross-sectional area.
D: The resistance of the wire is directly proportional to its length and inversely proportional to its diameter.
▶️Answer/Explanation
Answer: C
Explanation: The resistance \( R \) of a wire is given by \( R = \rho \frac{L}{A} \), where \( \rho \) is the resistivity, \( L \) is the length, and \( A \) is the cross-sectional area. Therefore, resistance is directly proportional to length and inversely proportional to cross-sectional area.
Question 26 (Subtopic: 4.2)
The diagram shows the current-voltage graph for a metal wire.
What can be deduced from the graph?
A: As voltage increases, the temperature of the wire increases.
B: As voltage increases, the temperature of the wire decreases.
C: As voltage increases, the resistance of the wire increases.
D: As voltage increases, the resistance of the wire remains constant.
▶️Answer/Explanation
Answer: D
Explanation: For a metal wire, the current-voltage graph is a straight line passing through the origin, indicating that the resistance remains constant as voltage increases. This is because the wire obeys Ohm’s Law (\( V = IR \)).
Question 27 (Subtopic: 4.2)
A battery is connected to a circuit. It is switched on for 1.0 minute. During that time, there is a current of 0.40 A in the circuit and the battery supplies a total of 48 J of energy. Which row gives the charge that passes and the electromotive force (e.m.f.) of the battery?
▶️Answer/Explanation
Answer: C
Explanation: The charge \( Q \) that passes is given by \( Q = It = 0.40 \, \text{A} \times 60 \, \text{s} = 24 \, \text{C} \). The e.m.f. \( E \) is given by \( E = \frac{W}{Q} = \frac{48 \, \text{J}}{24 \, \text{C}} = 2.0 \, \text{V} \).
Question 28 (Subtopic: 4.3)
The circuit diagram shows two identical lamps connected in parallel to a cell. Three ammeters, X, Y and Z, are also connected in the circuit, as shown.
Which statement about the current in X is correct?
A: It is equal to the current in Y and to the current in Z.
B: It is less than either the current in Y or the current in Z.
C: It is equal to the sum of the current in Y and the current in Z.
D: It is equal to the difference between the current in Y and the current in Z.
▶️Answer/Explanation
Answer: C
Explanation: In a parallel circuit, the total current from the cell (measured by ammeter X) is equal to the sum of the currents in the individual branches (measured by ammeters Y and Z). Therefore, the current in X is equal to the sum of the currents in Y and Z.
Question 29 (Subtopic: 4.3)
A student connects the circuit shown.
Which switches must be closed for the bell to ring without lighting the lamp?
A: 1 and 2 only
B: 1 and 3 only
C: 1, 3 and 4
D: 2, 3 and 4
▶️Answer/Explanation
Answer: B
Explanation: For the bell to ring without lighting the lamp, the circuit must be completed through the bell but not through the lamp. Therefore, switches 1 and 3 must be closed, while switch 2 (which controls the lamp) must remain open.
Question 30 (Subtopic: 4.5)
The diagram shows an a.c. generator.
The graph shows the potential difference (p.d.) between points X and Y plotted against time. A positive value of p.d. indicates that X is more positive than Y.
Which diagram shows the position of the coil at point P on the graph?
▶️Answer/Explanation
Answer: C
Question 31 (Subtopic: 4.5)
An electron moves into a uniform magnetic field. The arrow shows the initial direction of motion of the electron. The direction of the magnetic field is into the plane of the page.
In which direction does a force act on the electron when it enters the magnetic field?
A: into the page
B: out of the page
C: towards the bottom of the page
D: towards the top of the page
▶️Answer/Explanation
Answer: C
Explanation: The force on a moving electron in a magnetic field is given by the left-hand rule (since the electron is negatively charged). The force is perpendicular to both the direction of motion and the magnetic field. In this case, the force acts towards the bottom of the page.
Question 32 (Subtopic: 4.5)
Which statement about a transformer is correct?
A: There is an alternating current in the iron core from the primary coil to the secondary coil.
B: An alternating current in the iron core induces an alternating current in the secondary coil.
C: An alternating current in the primary coil induces a direct current in the secondary coil.
D: An alternating current in the primary coil induces an alternating voltage across the secondary coil.
▶️Answer/Explanation
Answer: D
Explanation: A transformer works on the principle of electromagnetic induction. An alternating current in the primary coil induces an alternating voltage across the secondary coil. There is no current in the iron core, and the current in the secondary coil is also alternating, not direct.
Question 33 (Subtopic: 5.1)
How are positive and negative ions formed from atoms?
▶️Answer/Explanation
Answer: C
Explanation: Positive ions are formed by removing electrons from an atom, while negative ions are formed by adding electrons to an atom. The nucleus remains unchanged in both cases.
Question 34 (Subtopic: 5.1)
A nucleus of element X is represented as \( _{26}^{56}\textrm{X}\).
Which is an isotope of element X?
Options:
A: \( _{56}^{26}\textrm{X} \)
B: \( _{26}^{54}\textrm{X} \)
C: \( _{24}^{56}\textrm{X} \)
D: \( _{28}^{54}\textrm{X}\)
▶️Answer/Explanation
Answer: B
Explanation: Isotopes of an element have the same number of protons (atomic number) but different numbers of neutrons (mass number). Therefore, \( \frac{54}{26}X \) is an isotope of \( \frac{56}{26}X \) because it has the same atomic number (26) but a different mass number (54).
Question 35 (Subtopic: 5.2)
A radioactive source is placed near a detector connected to a counter. 210 counts are recorded by the counter in 3 minutes. The background count rate is 20 counts per minute (cpm). What is the corrected count rate for the radioactive source?
A: 50 cpm
B: 70 cpm
C: 190 cpm
D: 270 cpm
▶️Answer/Explanation
Answer: A
Explanation: The total count rate is \( \frac{210 \, \text{counts}}{3 \, \text{minutes}} = 70 \, \text{cpm} \). Subtracting the background count rate of 20 cpm gives the corrected count rate for the radioactive source: \( 70 – 20 = 50 \, \text{cpm} \).
Question 36 (Subtopic: 5.2)
The background count rate measured by a radiation counter is 40 counts per minute (cpm). With the counter close to a radioactive source, the counter reading is 960 cpm. The half-life of the source is 20 minutes. What is the counter reading one hour later?
A: 115 cpm
B: 120 cpm
C: 155 cpm
D: 160 cpm
▶️Answer/Explanation
Answer: C
Question 37 (Subtopic: 6.1)
Which planet in our Solar System is nearest to the Sun and what is the nature of the planet?
▶️Answer/Explanation
Answer: A
Explanation: Mercury is the closest planet to the Sun and is classified as a rocky planet, not a gaseous one.
Question 38 (Subtopic: 6.1)
A space station orbits the Earth at a distance of 7000 km from the Earth’s centre. It makes 15 orbits in every 24-hour period. What is the speed of the space station in its orbit?
A: 2900 km/h
B: 4400 km/h
C: 8800 km/h
D: 27000 km/h
▶️Answer/Explanation
Answer: D
Question 39 (Subtopic: 6.2)
Which nuclear reaction powers a stable star?
A: nuclear fission of nuclei producing hydrogen
B: nuclear fission of a uranium nucleus into a krypton nucleus and a barium nucleus
C: nuclear fusion of a krypton nucleus and a barium nucleus into a uranium nucleus
D: nuclear fusion of hydrogen nuclei producing helium
▶️Answer/Explanation
Answer: D
Explanation: Stable stars are powered by nuclear fusion, specifically the fusion of hydrogen nuclei (protons) into helium nuclei. This process releases a tremendous amount of energy, which sustains the star’s luminosity and heat.
Question 40 (Subtopic: 6.2)
Which stages in the life cycle of a star are listed in the order that they occur?
A: interstellar dust cloud → stable star → protostar
B: protostar → red giant → stable star
C: red giant → white dwarf → protostar
D: stable star → red giant → white dwarf
▶️Answer/Explanation
Answer: D
Explanation: The correct order of stages in the life cycle of a star is: stable star → red giant → white dwarf. This sequence represents the main stages of stellar evolution for a star like the Sun.