Questions 1
(a) Topic – 9.b
(b) Topic-9.b
(c) Topic-9.b
(d) Topic-9.b
This question is about astrophysics.
(a) Which of these is a large collection of billions of galaxies?
A Milky Way
B nebula
C solar system
D universe
(b) Which of these is a correct unit for gravitational field strength, g?
A kilogram (kg)
B newton (N)
C newton kilogram (Nkg)
D newton per kilogram (N/kg)
(c) Which statement explains why the gravitational field strength on the Moon is less than the gravitational field strength on Earth?
A the Moon is further away from the Sun than the Earth
B the Moon has less atmosphere than the Earth
C the Moon has less mass than the Earth
D the Moon has a greater density than the Earth
(d) Describe the differences between the orbit of the Moon and the orbit of a comet. You may include a diagram to support your answer.
▶️Answer/Explanation
Ans
(a) D (universe);
A is incorrect because the Milky way is the name of a galaxy
B is incorrect because a nebula contains dust and gas
C is incorrect because a solar system contains stars and planets
(b) D (newton per kilogram);
A is incorrect because this is the unit of mass
B is incorrect because this is the unit of force
C is incorrect because this is the unit of the product of force and mass
(c) C (the Moon has less mass than the Earth); 1
A is incorrect because distance from the Sun has no effect on the gravitational field strength of the Moon/Earth
B is incorrect because an atmosphere does not affect gravitational field strength
D is incorrect because a greater density would give a larger gravitational field strength
(d) moon orbits Earth/a planet and comet orbits Sun/star;
moon’s orbit is (almost) circular/slightly elliptical and comet’s orbit is (very) elliptical;
Questions 2
Topic – 2.b
The diagram shows four graphs, P, Q, R and S. Each graph shows a different relationship between current and time.
The table gives descriptions of the relationships between current and time shown by graphs P, Q, R and S. Complete the table by giving the correct graph for each description. 
▶️Answer/Explanation
Ans
one mark for each correct row;;;;
Questions 3
(a) Topic – 5.c
(b) Topic-5.c
This question is about microwave ovens and microwaves.
(a) A microwave oven cooks some food. Diagram 1 represents a microwave emitted by the microwave oven.
(i) Determine the wavelength of the microwave.
(ii) The microwave has a frequency of 2.35 GHz. Show that the speed of the microwave is about \(3×10^8 m/s\).
(b) Diagram 2 shows a damaged microwave oven with a hole in the door.
This microwave oven should not be used as it is very dangerous. State a harmful effect from the microwaves if this oven is used.
▶️Answer/Explanation
Ans
(a) (i) wavelength in range 12 – 13 (cm) = 1 mark;
wavelength = 12.5 (cm) = 2 marks;;
(ii) substitution;
conversion of ‘G’ to \(10^9\) or 1 billion;
evaluation that would round to \(3 × 10^8\) given to 2
or more s.f.;
e.g.
speed = 2.35 × 12.5
\(speed = 2.35 × 10^9 × 12.5(× 10^{−2})\)
\(speed = 2.9…× 10^8 (m/s)\)
(b) internal heating of {tissue/organs/body};
Questions 4
(a) Topic – 2.c
(b) Topic – 2.c
(c) Topic – 2.c
(d) Topic – 2.c
This question is about a filament lamp.
(a) Which of these is the correct circuit symbol for a filament lamp?
(b) The filament lamp emits visible light. The table gives some statements about visible light. Place ticks (ü) in the boxes to show which statements are correct for visible light
(c) The diagram shows a ray of light from the filament lamp incident on the reflective side of a curved mirror.
Complete the diagram by drawing
(i) the normal line where the ray is incident on the mirror.
(ii) the reflected ray of light.
(d) The filament lamp is connected in a circuit with a switch and a battery of three cells.
(i) When the switch is on, the filament lamp transfers 120J of energy in a time of 3.0 minutes. Each cell has a voltage of 1.5V. Calculate the current in the filament lamp.
(ii) A small plotting compass is placed near the wires in the circuit. When the switch is turned on, the compass needle moves to a new position. Give a reason why the compass needle moves.
▶️Answer/Explanation
Ans
(a)
A is incorrect because it is an LED
C is incorrect because it is a motor
D is incorrect because it is an LDR
(b)
(c) (i) normal line drawn correctly at mirror surface;
(ii) ray drawn reflecting;
angle of reflection correct;
e.g.
(d) (i) substitution into E = I × V × t;
rearrangement;
evaluation;
e.g.
120 = current × (3×)1.5 × 3.0(×60)
current = 120 / 4.5 × 180
(current =) 0.15 (A)
(ii) idea that current in wire produces a magnetic field;
Questions 5
(a) Topic – 3.b
(b) Topic-3.b
(c) Topic-3.b
A student uses this apparatus to investigate energy transfer by conduction in metals.
This is the student’s method.
• attach four strips, each made of a different metal, to a wooden ring
• use wax to attach a metal tack to the end of each metal strip
• place the strips above a Bunsen burner
• light the Bunsen burner and start a stopwatch at the same time
• when enough energy has been transferred to the wax, it melts, causing the metal tack to fall
• record the time taken for each tack to fall
(a) Explain how the wooden ring makes the apparatus safer for the student to use.
(b) Describe how energy is transferred by conduction through the metal strips.
(c) The bar chart shows the results of the student’s investigation.
(i) Justify the use of a bar chart in this investigation.
(ii) State how the student could improve the reliability of their results.
(iii) The student concludes that iron is the best metal for transferring energy by conduction. Evaluate the student’s conclusion.
▶️Answer/Explanation
Ans
(a) idea that there is a risk of burning from apparatus;
wood is an insulator;
wood will not get (as) hot;
(b) idea that atoms in metal have vibrations;
idea that vibrations increase in speed/amplitude (when metal is heated);
idea that vibrations are passed (along the metal) between particles;
(c) (i) idea that metal is a discrete / categoric variable;
(ii) repeat the measurements;
calculate a mean / identify anomalies;
(iii) copper/aluminium/brass are better conductors;
(because) time taken (for tack to fall) is shorter / quicker;
Questions 6
(a) Topic – 1.b
(b) Topic-1.b
(a) The graph shows how the velocity of a ball rolling down a long ramp changes with time.
(i) Using the graph, calculate the acceleration of the ball.
(ii) State the feature of the graph that gives the distance travelled by the ball.
(iii) Calculate the distance travelled by the ball in 2.5 seconds.
(b) The table shows data for the ball after it has travelled for two different times.
A student suggests that these results obey the relationship:
\(\frac {distance}{time}^2 = constant\)
Use data from the table to deduce whether the results support this suggestion.
▶️Answer/Explanation
Ans
(a) (i) idea of acceleration = gradient;
correct substitution;
evaluation;
e.g.
acceleration = gradient
acceleration = 3.0 (-0) / 2.5 (-0)
acceleration = \(1.2 (m/s^2)\)
(ii) any reference to area;
(iii) any attempt at area of triangle;
correct area attempted;
evaluation;
e.g.
distance = area of triangle
distance = ½ × 3.0 × 2.5
distance = 3.8 (m)
(b) evaluation of either \((15/5^2)\) or \((60/10^2)\);
evaluation of second constant;
comparison of the two values to conclude suggestion supported;
Questions 7
(a) Topic – 8.b
(b) Topic-8.c
(c) Topic- 8.c
This question is about using carbon dating to find the age of pieces of wood.
(a) The equation shows how carbon-14 forms in the atmosphere
(i) State the name of particle X.
(ii) Carbon-14 decays by beta decay. State what happens to the number of protons and the number of neutrons in a carbon-14 nucleus when it decays.
(b) A scientist determines how the percentage of carbon-14 remaining in a sample of wood changes with time. The table shows the scientist’s data.
(i) Plot the scientist’s data on the grid.
(ii) Draw the curve of best fit.
(iii) Use the graph to determine the age of a sample of wood that has 36% of its carbon-14 remaining.
(c) Carbon-14 dating is inaccurate for samples of wood produced after 1950. This is because the concentration of carbon-14 in the atmosphere greatly increased due to nuclear weapons testing.
(i) A tree absorbs carbon-14 during its lifetime. A student suggests that trees grown after 1950 are contaminated with carbon-14. Give a reason why the student’s suggestion is correct.
(ii) Explain how nuclear weapons testing affects the determination of the age of a sample of wood produced after 1950.
▶️Answer/Explanation
Ans
(a) (i) proton;
(ii) protons increase {by 1 / to 7};
neutrons decrease {by 1 / to 7};
(b) (i) linear scales that take up ≥ 50% of the grid for both axes;
labelled axes with units;
all points plotted correctly within ½ small square;
(ii) smooth curve within ½ small square of each point;
e.g.,
(iii) indication on graph from 36% to curve;
(age =) 8400 (years);
(c) (i) idea that tree contains more carbon14/radioactive atoms than it would do normally/ eq;
(ii) samples will appear younger;
with any one from:
*idea that trees absorb more carbon-14 (from the atmosphere);
* more radioactive than ‘normal’/before 1950;
Questions 8
(a) Topic – 9.d
(b) Topic-9.b
A star has a circular orbit around the centre of a galaxy.
(a) The diagram shows an outline of the galaxy and the star’s position in the galaxy.
Draw an arrow on the diagram to show the force on the star that keeps the star in a circular orbit.
(b) (i) The speed of light is \(3.0×10^8m/s\). One light year is the distance light travels in one year. Show that one light year is approximately \(10^{16} m\).
[one year = \(3.2×10^7 s]\)
(ii) The star is 29000 light years away from the centre of the galaxy and has an orbital speed of 220km/s. Calculate the time period of the star’s orbit around the centre of the galaxy. Give your answer in standard form.
▶️Answer/Explanation
Ans
(a) arrow pointing inwards, in direction from star to centre of galaxy;
(b) (i) any evidence of distance = (average) speed × time;
correct evaluation given to at least 2s.f.;
e.g.
\((distance =) 3.0 (× 10^8) × 3.2 (× 10^7)\)
\((distance =) 9.6 × 10^{15}\)
(ii) substitution into given formula;
rearrangement;
evaluation and presentation in standard form;
e.g.
\(220 000 = 2 × π × (29 000 × 10^{16})/T\)
\(T = 2 × π × (29 000 × 10^{16})/220 000\)
\((T =) 8.3 × 10^{15} (s)\)
Questions 9
(a) Topic – 8.c
(b) Topic-8.c
Diagram 1 shows some of the stages of electricity generation in a nuclear power station.
(a) Nuclear fission takes place inside the reactor of the nuclear power station.
(i) Give the name of a fuel that could be used in the reactor.
(ii) Energy is released from the fuel in the reactor by nuclear fission. Describe the process of nuclear fission that takes place inside the reactor.
(b) High pressure steam transfers energy from the reactor to a turbine. The turbine spins as the steam passes through it. Diagram 2 shows a simplified generator connected to the turbine.
(i) Explain how electricity is generated by the generator.
(ii) At night the power station does not need to generate as much electricity. Suggest how the output of this generator could be reduced.
(iii) The generator produces alternating current. Describe the differences between alternating current (a.c.) and direct current (d.c.).
▶️Answer/Explanation
Ans
(a) (i) uranium / U;
(ii) neutron absorbed by (parent) nucleus;
nucleus splits;
releasing (daughter) nuclei / neutrons;
fission process repeats;
(b) (i) coil(s) rotate;
coil(s) cut magnetic field of magnet(s);
voltage is induced / eq;
(ii) any one of:
* reduce the strength of the magnetic field;
*fewer coils;
* rotate slower / reduce speed;
* reduce the flow/speed/pressure of steam;
* reduce rate of fission / reactor output;
(iii) a.c. changes direction continuously / eq;
d.c. has one direction;
Questions 10
(a) Topic – 2.c
(b) Topic-2.c
This question is about electrical resistors.
(a) Diagram 1 shows a 13kΩ resistor connected to a 5.8V battery.
(i) State the formula linking voltage, current and resistance.
(ii) Calculate the current in the resistor.
(b) Diagram 2 shows a 200Ω resistor connected in parallel with a 13kΩ resistor
(i) Complete the circuit diagram by adding a suitable meter to diagram 2 to measure the current in the 13kΩ resistor.
(ii) The switch in the circuit is closed. Explain what happens to the current in the 13kΩ resistor and the current in the battery.
▶️Answer/Explanation
Ans
(a) (i) voltage = current × resistance;
(ii) substitution;
rearrangement;
evaluation;
e.g.
\(5.8 = current × 13(× 10^3)\)
\((current =) 5.8 / 13(× 10^3)\)
(current =) 4.5 × 10⁻⁴ (A)
(b) (i) correct ammeter symbol in series with 13 kΩ resistor;
(ii) 13 kΩ resistor: 5
* voltage remains the same;
* so current stays the same;
battery:
* total voltage remains the same;
* (circuit) resistance is reduced;
* (therefore) current through battery increases;
Questions 11
(a) Topic – 4.b
(b) Topic-4.c
The diagram shows a simple barometer designed to measure atmospheric pressure.
(a) (i) State the formula linking pressure difference, height, density and gravitational field strength, g.
(ii) The total pressure at point X is 117kPa. The pressure of the trapped gas is 12kPa. Calculate the height of the liquid above point X.
[density of liquid = 1.36 × 104 kg/m³]
(b) The Sun shines onto the barometer, increasing the temperature of the trapped gas. The volume of the trapped gas remains constant.
(i) Explain why the pressure of the trapped gas increases as its temperature increases.
(ii) The temperature of the trapped gas increases from 23°C to 38°C. The pressure of the trapped gas is 12kPa when its temperature is 23°C. Calculate the pressure of the trapped gas when its temperature is 38°C.
▶️Answer/Explanation
Ans
(a) (i) pressure (difference) = height (of liquid) × density × g
(ii) pressure due to liquid = 117 − 12 or 105 seen;
substitution;
rearrangement;
evaluation;
e.g.
liquid pressure = 105 kPa
\(105 (000) = h × 1.36 × 10^4 × 10\)
\(h = 105 (000) / (1.36 × 10^5)\)
(height =) 0.772 (m)
(b) (i) speed/KE of particles increases; ignore particles gain energy idea that particles collide with wall(s) more frequently;
idea that particles collide with wall(s) with more force/harder;
(ii) conversion of both temperatures into kelvin;
substitution into given equation;
rearrangement;
evaluation;
e.g.
\(T_1 = 296 K\) and \(T_2 = 311 K\)
12/296 = \(p_2\) / 311
\(p_2\) = 311 × 12/296
\(p_2\) = 13 (kPa)
Questions 12
(a) Topic – 3.c
(b) Topic-3.c
The photograph shows a toy called a marble run.
A student lifts a marble from the table to the top of the marble run at point A. They release the marble from point A and it rolls through pipes to reach the bottom of the marble run at point B. The marble leaves the marble run at point B and rolls across the table. As the marble rolls, energy is transferred due to the different forces acting on the marble.
(a) Describe the energy transfers from before the student lifts the marble to when the marble reaches point B of the marble run.
(b) The student wants to measure how much energy the marble loses as it moves from point A to point B.
(i) The student needs to measure the speed of the marble as it leaves the marble run at point B. Describe a method the student could use to measure this speed.
(ii) The difference in height between point A and point B is 0.21m. The mass of the marble is 5.5g. The marble leaves the marble run at point B with a speed of 0.76m/s. Calculate the energy lost by the marble as it rolls from point A to point B.
▶️Answer/Explanation
Ans
(a) any five from: 5
MP1. chemical energy (store of student);
MP2. transferred mechanically;
MP3. (to) gravitational energy (store of marble);
MP4. transferred mechanically;
MP5. (to) kinetic energy (store of marble);
MP6. idea that thermal energy (store of marble) increases;
MP7. idea that thermal energy (store) of marble run / surroundings increases;
MP8. energy transferred to surroundings by radiation;
(b) (i) let marble roll across table for a known distance;
measure time taken;
use speed = distance / time;
OR
use of light gate;
connected to datalogger;
positioned so that (centre of) marble cuts beam(s);
(ii) substitution into GPE formula;
evaluation of GPE;
substitution into KE formula;
evaluation of KE;
subtraction to find energy lost;
e.g.
GPE = 0.0055 × 10 × 0.21
GPE = 0.01155 (J)
\(KE = 0.5 × 0.0055 × 0.76^2\)
KE = 0.0015884 (J)
energy lost = (0.01155 ― 0.0015884 =)
0.010 (J)