ATAR Physics Past Paper PDF 2023 School Curriculum and Standards Authority

2024/8268 Web version of 2023/66794...

2024/8268 Web version of 2023/66794 ATAR course examination, 2023 Question/Answer booklet PHYSICS Place one of your candidate identification labels in this box. Ensure the label is straight and within the lines of this box. WA student number: In figures In words Time allowed for this paper Number of additional Reading time before commencing work: ten minutes answer booklets used Working time: three hours (if applicable): Materials required/recommended for this paper To be provided by the supervisor This Question/Answer booklet Formulae and Data booklet To be provided by the candidate Standard items: pens (blue/black preferred), pencils (including coloured), sharpener, correction fluid/tape, eraser, ruler, highlighters Special items: up to three calculators, which do not have the capacity to create or store programmes or text, are permitted in this ATAR course examination, drawing templates, drawing compass and a protractor Important note to candidates No other items may be taken into the examination room. It is your responsibility to ensure that you do not have any unauthorised material. If you have any unauthorised material with you, hand it to the supervisor before reading any further. Copyright © School Curriculum and Standards Authority 2023 Ref: 23-068 *PHY* PHY PHYSICS 2 Structure of this paper Number of Number of Suggested Marks Percentage of Section questions questions to working time available examination available be answered (minutes) Section One 12 12 50 59 30 Short response Section Two 6 6 90 93 50 Problem-solving Section Three 2 2 40 41 20 Comprehension Total 100 DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF Instructions to candidates 1. The rules for the conduct of the Western Australian external examinations are detailed in the Year 12 Information Handbook 2023: Part II Examinations. Sitting this examination implies that you agree to abide by these rules. 2. Write your answers in this Question/Answer booklet preferably using a blue/black pen. Do not use erasable or gel pens. 3. You must be careful to confine your answers to the specific questions asked and to follow any instructions that are specific to a particular question. 4. When calculating numerical answers, show your working or reasoning clearly. Unless otherwise instructed, give final answers to three significant figures and include appropriate units where applicable. When estimating numerical answers, show your working or reasoning clearly. Give final answers to a maximum of two significant figures and include appropriate units where applicable. 5. Supplementary pages for planning/continuing your answers to questions are provided at the end of this Question/Answer booklet. If you use these pages to continue an answer, indicate at the original answer where the answer is continued, i.e. give the page number. 6. The Formulae and Data booklet is not to be handed in with your Question/Answer booklet. See next page  3 PHYSICS Section One: Short response 30% (59 Marks) This section has 12 questions. Answer all questions. Write your answers in the spaces provided. When calculating numerical answers, show your working or reasoning clearly. Unless otherwise instructed, give final answers to three significant figures and include appropriate units where applicable. When estimating numerical answers, show your working or reasoning clearly. Give final answers to a maximum of two significant figures and include appropriate units where applicable. Supplementary pages for planning/continuing your answers to questions are provided at the end of this Question/Answer booklet. If you use these pages to continue an answer, indicate at the original answer where the answer is continued, i.e. give the page number. Suggested working time: 50 minutes. DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF Question 1 (5 marks) A DC motor is attached to a 6.00 V supply, as shown in the diagram on the right. The square coil has a side length of 8.60 cm and contains 50 turns. The total resistance of the circuit is 3.00 Ω and it sits in a 3.70 × 10–3 T magnetic field. (a) Which way will the coil rotate when For copyright reasons this image cannot be observed from X? Circle your answer. reproduced in the online version of this document (1 mark) A. Clockwise B. Anticlockwise. (b) Calculate the magnitude of the initial torque on the coil in the position shown in the diagram. (4 marks) Answer Nm See next page PHYSICS 4 Question 2 (4 marks) N mg θ The free body diagram above shows a car going clockwise around a corner on a banked track without relying on friction. DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF (a) Complete the vector diagram, showing how these two forces result in a centripetal force. Indicate where the angle θ is on your diagram. (2 marks) mg N (b) With reference to your diagram in part (a), describe why increasing the angle of the track allows the cars to go around the same radius curve at a greater speed. (2 marks) See next page  5 PHYSICS Question 3 (4 marks) A 370 g single fluffy die on a string is hanging from a baby carriage travelling on a Melbourne tram. The tram accelerates away from the tram stop. At the point of acceleration, the angle between the string and the vertical is 15.5°. Calculate the magnitude of the acceleration of the tram. a 15.5° DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF Answer: m s–2 Question 4 (4 marks) Calculate the wavelength of a photon with an energy of 1.81 keV. Answer: m See next page PHYSICS 6 Question 5 (6 marks) h 20.0 m s –1 m.8 31.0 m 45 50.0° 3.50 m 1.50 × 102 m DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF A catapult is 1.50 × 102 m away from a 20.0 m high castle wall on top of a 31.0 m hill. It launches a metal ball at 50.0° to the horizontal 3.50 m above the ground at 45.8 m s–1. Calculate how far above the castle wall the ball passes (h). Answer: m See next page  7 PHYSICS Question 6 (6 marks) The photoelectric effect equation is 1 mv 2 = hf – W 2 max The maximum kinetic energy of a liberated electron is equal to the difference between the energy of the incoming photon and the work function of the metal target. Incident light Quartz window DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF Cathode Anode Ammeter Variable voltage Figure 1: Photoelectrons are released from a metal target in a vacuum tube (a) Describe how, and under what circumstances, electrons are liberated from the target by incoming photons. (2 marks) (b) Discuss how the maximum kinetic energy of the liberated electrons is experimentally determined. (4 marks) See next page PHYSICS 8 Question 7 (7 marks) The north pole of a bar magnet is moved at a constant speed of 0.370 m s–1 towards a coil of wire. The coil has seven turns and a cross sectional area of 0.0240 m2. The ends of the wire are connected to a galvanometer (which measures very small currents). (a) State Lenz’s law. (2 marks) DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF (b) With reference to Lenz’s law, explain why the needle in the galvanometer moves to the left, i.e. the current in the galvanometer flows right to left. (3 marks) (c) Explain why the emf induced in the coil is not constant, even though the speed of the magnet remains constant. (2 marks) See next page  9 PHYSICS Question 8 (6 marks) Edwin Hubble found that the further a galaxy is away from an observer, the faster it is receding. Below is a graph of data showing this relationship. 20 000 Recessional speed v (km s–1) 15 000 10 000 DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF 5000 10 20 30 Distance, d (Mpc) Using the graph above, estimate the distance in kilometres to a galaxy that is receding at 4.5% of the speed of light. Answer: km See next page PHYSICS 10 Question 9 (3 marks) Radio signal travelling from A to B A B Katya Rahul DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF A radio signal is emitted from Spaceship ‘A’ and arrives at Spaceship ‘B’. A and B are stationary with respect to Katya. In her frame of reference, A and B are a distance d1 apart, and the signal takes time t1 to travel. Rahul is moving parallel to the radio waves between A and B with constant velocity near the speed of light with respect to Katya and the two spaceships. In his frame of reference, A and B are a distance d2 apart, and the signal takes time t2 to travel. Derive an expression for d2 in terms of d1, t1 and t2. Show your reasoning and state any assumptions. (Hint: It is not necessary to use length contraction or time dilation.) Answer: d2 = See next page  11 PHYSICS Question 10 (4 marks) Estimate the de Broglie wavelength for a standard men’s basketball travelling at 10.0 m s–1. DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF Answer: m Question 11 (4 marks) The table below lists four subatomic particles. Identify the category to which they belong in the second column and state whether or not they are bound by the strong nuclear force in the third column. Category Bound by strong nuclear force Particle (meson, baryon or lepton) (yes or no) Proton Pion Neutrino Muon See next page PHYSICS 12 Question 12 (6 marks) A metal bar of mass m is falling through a uniform  horizontal magnetic field of strength B. The effective length of the bar in the field is l. The bar, which m maintains contact with the frictionless wire, completes an external circuit with a resistance of R. Derive v an expression for the velocity of the bar in terms of m, g, R, B and l given the velocity is constant. DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF R Bout of page Answer: v = End of Section One See next page  13 PHYSICS DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF This page has been left blank intentionally See next page PHYSICS 14 Section Two: Problem-solving 50% (93 Marks) This section has six questions. Answer all questions. Write your answers in the spaces provided. When calculating numerical answers, show your working or reasoning clearly. Unless otherwise instructed, give final answers to three significant figures and include appropriate units where applicable. When estimating numerical answers, show your working or reasoning clearly. Give final answers to a maximum of two significant figures and include appropriate units where applicable. Supplementary pages for planning/continuing your answers to questions are provided at the end of this Question/Answer booklet. If you use these pages to continue an answer, indicate at the original answer where the answer is continued, i.e. give the page number. Suggested working time: 90 minutes. DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF Question 13 (17 marks) I +q v A positive charge of 4.80 × 10–19 C is 35.0 cm below an extremely long straight wire carrying a current of 2.51 A to the left. The positive charge is moving parallel to the wire with a velocity of 1.57 × 104 m s–1 to the right, at the instant shown in the diagram above. (a) Calculate the strength of the magnetic field 35.0 cm from the wire. (3 marks) Answer: T See next page  15 PHYSICS (b) Calculate the force experienced by the particle as it moves through this magnetic field. Include the direction of the force in your answer. If you could not obtain an answer to part (a), use 2.51 × 10–6 T. (3 marks) DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF Answer: N Direction: (c) With reference to two relevant equations on the data sheet, discuss why the path the particle takes is not circular. (5 marks) See next page PHYSICS 16 Question 13 (continued) (d) The particle is now moving midway between two wires with equal currents flowing in the same direction. In this position, the particle experiences no net force. I v +q I DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF (i) The diagram below shows the view of the wires from the front left. The current is flowing out of the page. Draw the composite magnetic field generated by the two current­‑carrying wires. Indicate clearly the location of the charge q on your diagram. (4 marks) A spare diagram is provided at the end of this booklet. If you need to use it, cross out this attempt and indicate that you have redrawn it on the spare diagram. (ii) Describe why the charge q experiences no net force in this position. (Ignore any gravitational effects.) (2 marks) See next page  17 PHYSICS DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF This page has been left blank intentionally See next page PHYSICS 18 Question 14 (13 marks) 0.700 c A S B 0.700 c Two 5.00 × 102 m long identical spaceships, ‘A’ and ‘B’, pass by an observer S while moving in opposite directions. The observer S measures the velocity of spaceship A as 0.700 c and spaceship B as –0.700 c. (a) (i) Calculate the velocity of A (in m s–1) as measured by B. (4 marks) DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF Answer: m s–1 (ii) Explain why the magnitude of the velocity of B as measured by A would be the same as your answer for part (a)(i), only in the opposite direction. (3 marks) See next page  19 PHYSICS (b) Calculate the duration of one second on A as measured by the observer S. (3 marks) DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF Answer: s (c) Calculate the length of B as measured by A. If you could not obtain an answer to part (a)(i), use 0.870 c. (3 marks) Answer: m See next page PHYSICS 20 Question 15 (14 marks) Larry Mo Stoogus Curly A recently discovered planet (Stoogus) in a distant solar system has three moons (Larry, Curly and Mo) orbiting at different distances. Stoogus has a mass of 2.37 × 1024 kg and a day on Stoogus lasts 7.50 Earth hours. Assume all three moons have circular orbits as their masses are DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF insignificant compared to that of Stoogus. (a) Curly is a geosynchronous satellite that orbits above one specific spot on Stoogus’ surface. Calculate the radius of Curly’s orbit. (5 marks) Answer: m (b) The gravitational field strength that Mo experiences due to Stoogus is 4.50 × 10–3 m s–2. Calculate the distance between the centre of mass of Mo and the centre of mass of Stoogus. (4 marks) Answer: m See next page  21 PHYSICS (c) (i) Derive the mathematical relationship between a moon’s orbital speed v and its distance r from the planet’s centre of mass. (3 marks) DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF Answer: (ii) Use this relationship from part (c)(i) to identify which moon of Stoogus has the greatest orbiting speed. Justify your answer. (2 marks) See next page PHYSICS 22 Question 16 (18 marks) A group of students set up the apparatus shown in the diagram above to measure the mass per DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF unit length of a thin and strong steel wire. On each successive trial, they increased the mass of the counterweight M, further stretching the wire. They then plucked the steel wire and measured the frequency of the vibrating wire using a strobe light. The length L of the vibrating portion of the wire, shown in the diagram above, was 0.450 m. Their results are given in the table below. Mass (kg) 1.50 2.00 2.50 3.00 3.50 4.00 Frequency (Hz) 105 120 135 150 160 170 The students observed the wire vibrating in its fundamental mode, where wavelength λ = 2L, and substituted this into the wave equation v = λf. They also used the following equation for the speed v of a wave along a wire under tension: T v where T is the tension in the wire (in N) and µ is the mass per unit length (in kg m–1).  Using these equations they derived the relationship below. T = (4L2 µ) f 2 (a) Show how the students derived this relationship. (4 marks) See next page  23 PHYSICS The students then manipulated their data so as to graph this relationship and produce a straight line. (b) Make the adjustments to the data and place the results in the table below. Give your answers to three significant figures and express f 2 in scientific notation. (4 marks) Mass (kg) 1.50 2.00 2.50 3.00 3.50 4.00 Tension (N) f 2 (Hz2) (c) Graph your data on the grid below. Include a line of best fit. (3 marks) DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF 40 30 Tension (N) 20 10 5 10 15 20 25 30 f × 10 (Hz2) 2 3 A spare grid is provided at the end of this Question/Answer booklet. If you need to use it, cross out this attempt and indicate that you have redrawn it on the spare grid. See next page PHYSICS 24 Question 16 (continued) (d) Use the gradient of your line of best fit to calculate the mass per unit length in kg m–1 of the steel wire. Indicate clearly the two points used and express your answer to the appropriate number of significant figures. (5 marks) DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF Answer: kg m–1 (e) In the summary of their report, the students had to identify any variables that could affect the accuracy of their value. They identified correctly an important assumption they had made, which may have caused their value to be slightly different from the theoretical value. This had nothing to do with human error, inaccurate equipment, atmospheric conditions or calibration of instruments. Describe their assumption. (2 marks) See next page  25 PHYSICS DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF This page has been left blank intentionally See next page PHYSICS 26 Question 17 (14 marks) A uniform garden gate is attached to its support by two hinges (T and B). The top hinge (T ) is fixed 20.0 cm below the top of the gate and the bottom hinge is fixed to the bottom of the gate. The gate has a mass of 25.7 kg. It is 1.00 m wide and 1.40 m tall. Note: The top hinge takes all of the vertical weight force of the gate. The bottom hinge keeps the gate lined up correctly. By taking moments around B, calculate the (a) horizontal component of the reaction force of T on the gate. Include a direction in your answer. (5 marks) DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF Answer: N Direction: (b) Calculate the overall reaction force of T on the gate. Include an angle to the horizontal in your answer. If you could not obtain an answer to part (a), use 1.40 × 102 N. (5 marks) Answer: N at ° to the horizontal See next page  27 PHYSICS (c) Discuss how the angle in part (b) would be affected if the top hinge was fixed at the top of the gate. Include a mathematical expression in your answer. (4 marks) DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF See next page PHYSICS 28 Question 18 (17 marks) v 4.00 × 10–2 m In an evacuated chamber, a proton enters an electric field at a speed of 1.79 × 106 m s–1 midway between two charged parallel plates and is initially moving parallel to them. The plates are 4.00 × 10–2 m apart and there is a potential difference of 4.80 × 103 V between them. (a) (i) Calculate the downward force exerted on the proton by the electric field. (3 marks) DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF Answer: N (ii) Choose which mathematical relationship (A, B, C or D) describes the path taken by the proton when it enters the field. Circle your answer. (1 mark) 1 A. y ∝ x B. y ∝ C. y ∝ x D. y ∝ x2 x (b) Given that the proton does not exit the field before hitting the bottom plate, how far from the right hand end of the bottom plate does the proton land? Ignore any effects due to gravity. (7 marks) Answer: m See next page  29 PHYSICS (c) Calculate the velocity of the proton just before it strikes the bottom plate. Include an angle in your answer. (6 marks) DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF Answer: m s–1 at ° to the horizontal End of Section Two See next page PHYSICS 30 Section Three: Comprehension 20% (41 Marks) This section has two questions. You must answer both questions. Write your answers in the spaces provided. When calculating numerical answers, show your working or reasoning clearly. Unless otherwise instructed, give final answers to three significant figures and include appropriate units where applicable. When estimating numerical answers, show your working or reasoning clearly. Give final answers to a maximum of two significant figures and include appropriate units where applicable. Supplementary pages for planning/continuing your answers to questions are provided at the end of this Question/Answer booklet. If you use these pages to continue an answer, indicate at the original answer where the answer is continued, i.e. give the page number. Suggested working time: 40 minutes. DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF Question 19 (21 marks) The Big European Bubble Chamber (BEBC) Figure 1: The BEBC Fundamental particles are extremely small and usually fast moving. This makes them hard to detect. If they are passed through a medium which records the path of their movement, new particles can be identified by their behaviour. The products of collisions between known particles can also be observed. One such medium is superheated hydrogen. A superheated liquid is one which is held just above its natural boiling point. These liquids are unstable and ‘boil’ when the slightest disturbance is experienced. Charged particles moving at high speeds will cause the formation of tiny bubbles in the hydrogen and therefore leave a trace of the particles’ trajectory. An example of this is shown in Figure 2 on page 31. See next page  31 PHYSICS For copyright reasons this image cannot be reproduced in the online version of this document but may be viewed at the following link http://model31.pl/en/electron-and-positron-similarities-and-differences/ Figure 2: The collision of a gamma ray and a hydrogen atom’s electron in a bubble chamber A gamma ray enters from the left and collides with the electron of a hydrogen atom. It is neutral DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF so there is no trace. Its path is shown as a dotted line. The gamma ray loses some energy which creates an electron and its antiparticle, a positron. The electron from the hydrogen atom recoils to the bottom right. Because the chamber is in a strong magnetic field, the charged particles spiral in different directions and with different momenta. Figure 3: The collision between a positive pion and a proton in a bubble chamber In Figure 3, a positive meson called a pion (π +) enters from the left and strikes a proton at A. The pion and the proton become two new pions, a kaon (K0) and a lambda particle (Λ). Both the kaon and lambda particles are neutral so they travel in straight lines and do not leave a trail. The lambda particle decays into a proton and a negative pion at B. The kaon decays into a positive and a negative pion at C. See next page PHYSICS 32 Question 19 (continued) In summary, a proton and one pion have been converted into a proton and five pions. There are three varieties of pion: +, –, and 0. The antiparticle of the positive pion is the negative pion and the π 0 is its own antiparticle. (a) Discuss how the diagram in Figure 2 on page 31, shows that the two charged particles produced in the collision have different momenta. (4 marks) DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF (b) Explain how one proton and one pion can be converted into one proton and five pions. (3 marks) (c) Why do the lambda and kaon particles leave no tracks in the bubble chamber? (2 marks) See next page  33 PHYSICS (d) Is charge conserved in the overall reaction? Justify your answer with a calculation of the total charge before and after the collision. (4 marks) DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF (e) List a possible quark composition of the π + and π – particles. (3 marks) Particle Quark composition π+ π– (f) The approximate mass of the incoming π + is 2.48 × 10–28 kg. If the radius of the circular path the pion is taking is 2.30 mm and it has a forward velocity of 3.70 × 105 m s–1, estimate the strength of the magnetic field in the bubble chamber. (5 marks) Answer: T See next page PHYSICS 34 Question 20 (20 marks) Polarisation of light Figure 1: Pair of polarised sunglasses DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF When you buy a pair of polarised sunglasses, the main purpose they serve is to reduce the intensity of light hitting your eyes. How they achieve this is described below. ter ising fil Polar Figure 2: Randomly polarised light passing through a polarising filter Light waves are a combination of oscillating magnetic and electric fields. As the magnetic field changes, it induces a changing electric field, which in turn induces a magnetic field and so on. A beam of light consists of transverse waves oscillating in all directions around the line of propagation. A polarised filter can be thought of as a series of slits that only allows those waves to pass through with their electric fields oscillating in the same direction as the axis in the filter. See next page  35 PHYSICS But the filters do not have actual slits in them. The material consists of long chain polymers. Electrons in these chains are free to move along the chains but not between them. A light wave’s electric field does work on these electrons and causes them to absorb the wave’s energy. Therefore, light waves which are polarised parallel to the chains get absorbed and those travelling perpendicular pass through undisturbed. Those travelling at an angle to the chains are partially absorbed. The axis of the filter is perpendicular to the chains. DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF Figure 3: Axis of polarisation is perpendicular to the aligned long chain polymer molecules Figure 4 illustrates this point. Only the component of the electric field parallel to the axis of a polarising filter is allowed to pass. θ In the diagram, angle θ represents the angle E between the direction of polarisation of incident light and the axis of a polarising filter. After passing through the filter, the amplitude of the electric field has been reduced by a factor of E cos(θ ) cos θ. ter ising fil Since intensity of a wave is proportional P olar to its amplitude squared, the intensity I of the transmitted wave is related to the initial Figure 4: Polarising filter intensity I0 of the incident light by the following with angle θ shown relationship, known as Malus’ Law: I = I0 cos2 θ. A single polarising filter reduces the wave’s intensity by exactly 50.0%. Intensity is measured in watts per square metre (W m–2). See next page PHYSICS 36 Question 20 (continued) (a) With reference to Figure 3 on page 35, discuss how unpolarised light can become polarised. (4 marks) DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF (b) Define the axis of a polarising filter and describe its function. (2 marks) (c) According to Malus’ Law, at what angle to the direction of polarisation of the incident light should the axis of a polarising filter be oriented in order to (i) allow the light to pass without reduction in intensity? (1 mark) Answer: ° (ii) completely block the passage of the light? (1 mark) Answer: ° See next page  37 PHYSICS (d) Use Malus’ Law to calculate the angle between the direction of polarisation of the incident light and the axis of a polarising filter if the incoming light has its intensity reduced by 75.0%. (4 marks) Answer: ° (e) DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF A group of students placed two polarising filters at right angles and saw no light being transmitted. They placed a third filter between the first two at 45.0° to each one and noticed light was transmitted. (i) Explain how inserting the third filter allowed light to hit the screen when no light was hitting it before. (3 marks) (ii) What percentage of the original light’s intensity is hitting the screen with the third filter in place? (2 marks) Answer: % See next page PHYSICS 38 Question 20 (continued) (f) A photon’s energy is given by E = hf. When light passes through a polarising filter, the total energy transmitted is reduced but the frequency of each photon remains the same. Using the particle model of light, account for the reduction in transmitted energy. (3 marks) DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF End of questions PHYSICS 39 Supplementary page Question number: DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF  PHYSICS Question number: Supplementary page 40 DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF PHYSICS 41 Supplementary page Question number: DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF  PHYSICS Question number: Supplementary page 42 DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF  43 PHYSICS Spare diagram for Question 13(d)(i) DO NOT WRITE IN THIS AREA AS IT WILL BE CUT OFF Spare grid for Question 16(c) 40 30 Tension (N) 20 10 5 10 15 20 25 30 f 2 × 103 (Hz2)  ACKNOWLEDGEMENTS Question 1 Figure 2 adapted from: Excel@Physics. (n.d.). [Diagram of DC motor]. Retrieved April, 2023, from http://www.excelatphysics.com/magnetism- and-electromagnetism-question.html Question 19 Figure 1: Zenz, S. (2005). Big European Bubble Chamber [Photograph]. Retrieved April, 2023, from https://commons.wikimedia. org/wiki/File:Big_European_Bubble_Chamber.jpg Used under a Creative Commons Attribution-ShareAlike 3.0 Unported licence. Figure 2: Walo, R. (2018). Trails of an Electron and Positron in a Bubble Chamber [Diagram]. Retrieved April, 2023, from http://model31.pl/en/electron-and-positron-similarities-and-differences/ Question 20 Figure 1: Dhumal, N. (2015). Red Lens Sunglasses on Sand Near sea at Sunset Selective Focus Photography [Photograph]. Retrieved April, 2023, from https://www.pexels.com/photo/red-lens-sunglasses-on- sand-near-sea-at-sunset-selective-focus-photography-46710/ Paragraphs 4 and 5 adapted from: Urone, P. P., & Hinrichs, R. (2012). 27.8 Polarization. In College Physics. Retrieved April, 2023, from https://openstax.org/books/college-physics/pages/27-8-polarization Used under a Creative Commons Attribution 4.0 licence. Figure 4 adapted from Urone, P. P., & Hinrichs, R. (2012). Figure 27.42 A polarizing filter […] its axis [Diagram]. Retrieved April, 2023, from https://openstax.org/books/college-physics/pages/27-8- polarization Used under a Creative Commons Attribution 4.0 licence. This document – apart from any third party copyright material contained in it – may be freely copied, or communicated on an intranet, for non-commercial purposes in educational institutions, provided that it is not changed and that the School Curriculum and Standards Authority (the Authority) is acknowledged as the copyright owner, and that the Authority’s moral rights are not infringed. Copying or communication for any other purpose can be done only within the terms of the Copyright Act 1968 or with prior written permission of the Authority. Copying or communication of any third party copyright material can be done only within the terms of the Copyright Act 1968 or with permission of the copyright owners. Any content in this document that has been derived from the Australian Curriculum may be used under the terms of the Creative Commons Attribution 4.0 International (CC BY) licence. An Acknowledgements variation document is available on the Authority website. Published by the School Curriculum and Standards Authority of Western Australia 303 Sevenoaks Street CANNINGTON WA 6107