AQA-84032-QP-JUN14.pdf

Centre Number Candidate Number For Examiner’s UseSurname Other Names Examiner’s Initials Candidate Signature Question Mark 1 AQA Level 1/2 Certificate June 2014 2 3 Physics 8403/2 4 Paper 2 5 6 Thursday 12 June 2014 9.00 am to 10.30 am TOTAL For this paper you must have:  a ruler  a calculator  the Physics Equations Sheet (enclosed). Time allowed  1 hour 30 minutes A Instructions  Use black ink or black ball-point pen.  Fill in the boxes at the top of this page.  Answer all questions.  You must answer the questions in the spaces provided. Do not write outside the box around each page or on blank pages.  Do all rough work in this book. Cross through any work you do not want to be marked. Information  The marks for questions are shown in brackets.  The maximum mark for this paper is 90.  You are expected to use a calculator where appropriate.  You are reminded of the need for good English and clear presentation in your answers.  Question 5(e) should be answered in continuous prose. In this question you will be marked on your ability to: – use good English – organise information clearly – use specialist vocabulary where appropriate. Advice  In all calculations, show clearly how you work out your answer. (Jun148403201) G/TI/104663/Jun14/E5 8403/2  2 Do not write outside the box There are no questions printed on this page DO NOT WRITE ON THIS PAGE ANSWER IN THE SPACES PROVIDED (02) G/Jun14/8403/2  3 Do not write outside the box Answer all questions in the spaces provided. 1 Figure 1 shows a set of tuning forks. Figure 1 Prong Handle A tuning fork has a handle and two prongs. It is made from metal. When the prongs are struck on a hard object, the tuning fork makes a sound wave with a single frequency. The frequency depends on the length of the prongs. 1 (a) Use the correct answer from the box to complete each sentence. [2 marks] direction loudness pitch speed The frequency of a sound wave determines its ............................................................... . The amplitude of a sound wave determines its ............................................................... . Question 1 continues on the next page Turn over  (03) G/Jun14/8403/2  4 Do not write outside the box 1 (b) Each tuning fork has its frequency engraved on it. A student measured the length of the prongs for each tuning fork. Some of her data is shown in Table 1. Table 1 Frequency Length of prongs in hertz in cm 320 9.5 384 8.7 480 7.8 512 7.5 1 (b) (i) Describe the pattern shown in Table 1. [1 mark] ............................................................................................................................................ ............................................................................................................................................ 1 (b) (ii) Figure 2 shows a full-size drawing of a tuning fork. Figure 2 Length of prongs Measure and record the length of the prongs. [1 mark] Length of prongs = ............................. cm (04) G/Jun14/8403/2  5 Do not write outside the box 1 (b) (iii) Use the data in Table 1 to estimate the frequency of the tuning fork in Figure 2. Explain your answer. [3 marks] ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ Estimated frequency = ............................. Hz 1 (c) Ultrasound waves are used in hospitals. 1 (c) (i) Use the correct answer from the box to complete the sentence. [1 mark] electronic hydraulic radioactive Ultrasound waves can be produced by ........................................... systems. 1 (c) (ii) The frequency of an ultrasound wave used in a hospital is 2  106 Hz. It is not possible to produce ultrasound waves of this frequency using a tuning fork. Explain why. [2 marks] ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ Question 1 continues on the next page Turn over  (05) G/Jun14/8403/2  6 Do not write outside the box 1 (d) Figure 3 shows a tuning fork and a microphone. The microphone is connected to an oscilloscope. Figure 3 When the tuning fork is struck and then placed in front of the microphone, a trace appears on the oscilloscope screen. (06) G/Jun14/8403/2  7 Do not write outside the box Figure 4 shows part of the trace on the screen. Figure 4 Each horizontal division in Figure 4 represents a time of 0.0005 s. What is the frequency of the tuning fork? Use the correct equation from Section A of the Physics Equations Sheet. [3 marks] ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ Frequency = ...................................... Hz ____ 13 Turn over for the next question Turn over  (07) G/Jun14/8403/2  8 Do not write outside the box 2 Visible white light consists of several different colours. Figure 5 shows white light passing through a triangular glass prism. The white light splits up into different colours. Two of the colours are shown. Figure 5 White light Red light Violet light Glass 2 (a) (i) Use the correct answer from the box to complete the sentence. [1 mark] deflection diffraction dispersion The process in which white light is split up into different colours is called ..................................................... . 2 (a) (ii) Visible light is part of the electromagnetic spectrum. Figure 6 shows part of the electromagnetic spectrum. Figure 6 Infrared Visible Ultraviolet Three of the colours of visible light are green, red and violet. Place these colours in order of increasing wavelength. [1 mark] ......................................... ......................................... ......................................... Smallest wavelength Largest wavelength (08) G/Jun14/8403/2  9 Do not write outside the box 2 (b) Figure 7 shows white light being refracted at the first surface of the triangular glass prism. The two refracted rays shown are for red light and violet light. Figure 7 Air Glass A i B C The angle of incidence is labelled i. The other angles are labelled A, B and C. 2 (b) (i) What is the name given to the dashed line? [1 mark] ............................................................................................................................................ 2 (b) (ii) Which angle, A, B or C, is the angle of refraction for violet light? [1 mark] Write the correct answer in the box. Question 2 continues on the next page Turn over  (09) G/Jun14/8403/2  10 Do not write outside the box 2 (b) (iii) The refractive index of a particular glass is different for different colours of light. Explain why. [3 marks] ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ 2 (c) Table 2 shows the refractive index values of a particular glass for different colours of light. Table 2 Refractive Colour index Red 1.509 Green 1.515 Violet 1.521 2 (c) (i) Using the information in Table 2, state how the refractive index of the glass varies with the wavelength of the light. [1 mark] ............................................................................................................................................ ............................................................................................................................................ (10) G/Jun14/8403/2  11 Do not write outside the box 2 (c) (ii) Use the data in Table 2 to calculate the speed of green light in the glass. [2 marks] speed of light in a vacuum refractive index = speed of light in glass Speed of green light in a vacuum = 3.00  108 m/s. ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ Speed of green light in the glass = ............................................... m/s 2 (d) Figure 8 shows apparatus that can be used to find the refractive index for glass. Figure 8 Ray box emitting white light Glass block Protractor This apparatus cannot be used to get the results shown in Table 2. Give two reasons why. [2 marks] 1 ......................................................................................................................................... ............................................................................................................................................ 2 ......................................................................................................................................... ............................................................................................................................................ Question 2 continues on the next page Turn over  (11) G/Jun14/8403/2  12 Do not write outside the box 2 (e) Figure 9 shows violet light within a glass block. Figure 9 Glass Air 2 (e) (i) Describe and explain what happens to the violet light as it meets the boundary between glass and air. [4 marks] ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ 2 (e) (ii) Use data from Table 2 to calculate the critical angle for violet light in glass. Use the correct equation from Section B of the Physics Equations Sheet. [3 marks] ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ Critical angle = ............................ degrees ____ 19 (12) G/Jun14/8403/2  13 Do not write outside the box 3 Different radioactive isotopes have different values of half-life. 3 (a) What is meant by the ‘half-life’ of a radioactive isotope? [1 mark] ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ 3 (b) Figure 10 shows how the count rate from a sample of a radioactive isotope varies with time. Figure 10 80 60 Count rate in counts 40 per minute 20 0 0 20 40 60 80 100 120 Time in days Use information from Figure 10 to calculate the half-life of the radioactive isotope. Show clearly on Figure 10 how you obtain your answer. [2 marks] Half-life = ...................................... days Question 3 continues on the next page Turn over  (13) G/Jun14/8403/2  14 Do not write outside the box 3 (c) Table 3 shows data for some radioactive isotopes that are used in schools. Table 3 Radioactive Type of radiation Half-life in isotope emitted years Americium-241 Alpha and gamma 460 Cobalt-60 Gamma 5 Radium-226 Alpha, beta and gamma 1600 Strontium-90 Beta 28 Thorium-232 Alpha and beta 1.4 x 1010 3 (c) (i) State which radioactive isotope in Table 3 emits only radiation that is not deflected by a magnetic field. Give a reason for your choice. [2 marks] ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ (14) G/Jun14/8403/2  15 Do not write outside the box 3 (c) (ii) Figure 11 shows a radioactive isotope being used to monitor the thickness of paper during production. Figure 11 Rollers Radioactive isotope Paper Detector State which radioactive isotope in Table 3 should be used to monitor the thickness of the paper. Explain your choice. [3 marks] ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ 3 (c) (iii) All the radioactive isotopes in Table 3 have practical uses. State which source in Table 3 would need replacing most often. Explain your choice. [3 marks] ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ Question 3 continues on the next page Turn over  (15) G/Jun14/8403/2  16 Do not write outside the box 3 (c) (iv) When the radioactive isotopes are not in use, they are stored in lead-lined wooden boxes. The boxes reduce the level of radiation that reaches the surroundings. Figure 12 shows two of these boxes. Figure 12 State one source from Table 3 which emits radiation that could penetrate the box. Explain your answer. [3 marks] ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ____ 14 (16) G/Jun14/8403/2  17 Do not write outside the box 4 If a fault develops in an electrical circuit, the current may become too great. The circuit needs to be protected by being disconnected. A fuse or a circuit breaker may be used to protect the circuit. One type of circuit breaker is a Residual Current Circuit Breaker (RCCB). 4 (a) (i) Use the correct answer from the box to complete the sentence. [1 mark] earth live neutral A fuse is connected in the ........................................... wire. 4 (a) (ii) Use the correct answer from the box to complete the sentence. [1 mark] are bigger are cheaper react faster RCCBs are sometimes preferred to fuses because they ........................................... . 4 (a) (iii) RCCBs operate by detecting a difference in the current between two wires. Use the correct answer from the box to complete the sentence. [1 mark] earth and live earth and neutral live and neutral The two wires are the .............................................................................. wires. Question 4 continues on the next page Turn over  (17) G/Jun14/8403/2  18 Do not write outside the box 4 (b) An RCCB contains an iron rocker and a coil. A student investigated how the force of attraction, between a coil and an iron rocker, varies with the current in the coil. She supported a coil vertically and connected it in an electrical circuit, part of which is shown in Figure 13. Figure 13 Iron rocker Small mass Pivot Coil She put a small mass on the end of the rocker and increased the current in the coil until the rocker balanced. She repeated the procedure for different masses. Some of her results are shown in Table 4. Table 4 Current needed for the Mass rocker to balance in in grams amps 5 0.5 10 1.0 15 1.5 20 2.0 (18) G/Jun14/8403/2  19 Do not write outside the box 4 (b) (i) State two extra components that must have been included in the circuit in Figure 13 to allow the data in Table 4 to be collected. Give reasons for your answers. [4 marks] ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ 4 (b) (ii) A teacher said that the values of current were too high to be safe. Suggest two changes that would allow lower values of current to be used in this investigation. [2 marks] Change 1 ........................................................................................................................... ............................................................................................................................................ Change 2 ........................................................................................................................... ............................................................................................................................................ ____ 9 Turn over for the next question Turn over  (19) G/Jun14/8403/2  20 Do not write outside the box There are no questions printed on this page DO NOT WRITE ON THIS PAGE ANSWER IN THE SPACES PROVIDED (20) G/Jun14/8403/2  21 Do not write outside the box 5 (a) A company is developing a system which can heat up and melt ice on roads in the winter. This system is called ‘energy storage’. During the summer, the black surface of the road will heat up in the sunshine. This energy will be stored in a large amount of soil deep under the road surface. Pipes will run through the soil. In winter, cold water entering the pipes will be warmed and brought to the surface to melt ice. The system could work well because the road surface is black. Suggest why. [1 mark] ............................................................................................................................................ ............................................................................................................................................ 5 (b) (i) What is meant by specific latent heat of fusion? [2 marks] ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ 5 (b) (ii) Calculate the amount of energy required to melt 15 kg of ice at 0 °C. Specific latent heat of fusion of ice = 3.4  105 J/kg. Use the correct equation from Section B of the Physics Equations Sheet. [2 marks] ............................................................................................................................................ ............................................................................................................................................ Energy = ...................................... J Question 5 continues on the next page Turn over  (21) G/Jun14/8403/2  22 Do not write outside the box 5 (c) Another way to keep roads clear of ice is to spread salt on them. When salt is added to ice, the melting point of the ice changes. A student investigated how the melting point of ice varies with the mass of salt added. Figure 14 shows the equipment that she used. Figure 14 Thermometer Beaker Crushed ice The student added salt to crushed ice and measured the temperature at which the ice melted. 5 (c) (i) State one variable that the student should have controlled. [1 mark] ............................................................................................................................................ ............................................................................................................................................ (22) G/Jun14/8403/2  23 Do not write outside the box 5 (c) (ii) During the investigation the student stirred the crushed ice. Suggest two reasons why. Tick () two boxes. [2 marks] Tick () To raise the melting point of the ice To lower the melting point of the ice To distribute the salt throughout the ice To keep all the ice at the same temperature To reduce energy transfer from the surroundings to the ice 5 (c) (iii) Table 5 shows the data that the student obtained. Table 5 Mass of salt added in grams 0 10 20 Melting point of ice in °C 0 −6 −16 Describe the pattern shown in Table 5. [1 mark] ............................................................................................................................................ ............................................................................................................................................ Question 5 continues on the next page Turn over  (23) G/Jun14/8403/2  24 Do not write outside the box 5 (d) Undersoil electrical heating systems are used in greenhouses. This system could also be used under a road. A cable just below the ground carries an electric current. One greenhouse system has a power output of 0.50 kW. Calculate the energy transferred in 2 minutes. Use the correct equation from Section C of the Physics Equations Sheet. [3 marks] ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ Energy transferred = ...................................... J (24) G/Jun14/8403/2  25 Do not write outside the box 5 (e) In this question you will be assessed on using good English, organising information clearly and using specialist terms where appropriate. A local council wants to keep a particular section of a road clear of ice in the winter. Describe the advantages and disadvantages of keeping the road clear of ice using: ● energy storage ● salt ● undersoil electrical heating. [6 marks] ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ Extra space ........................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ____ ............................................................................................................................................ 18 Turn over for the next question Turn over  (25) G/Jun14/8403/2  26 Do not write outside the box 6 A student investigated the behaviour of springs. She had a box of identical springs. 6 (a) When a force acts on a spring, the shape of the spring changes. The student suspended a spring from a rod by one of its loops. A force was applied to the spring by suspending a mass from it. Figure 15 shows a spring before and after a mass had been suspended from it. Figure 15 Before After Rod Loop Coils Mass 6 (a) (i) State two ways in which the shape of the spring has changed. [2 marks] 1 ......................................................................................................................................... 2 ......................................................................................................................................... 6 (a) (ii) No other masses were provided. Explain how the student could test if the spring was behaving elastically. [2 marks] ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ (26) G/Jun14/8403/2  27 Do not write outside the box 6 (b) In a second investigation, a student took a set of measurements of force and extension. Her results are shown in Table 6. Table 6 Force in newtons 0.0 1.0 2.0 3.0 4.0 5.0 6.0 Extension in cm 0.0 4.0 12.0 16.0 22.0 31.0 6 (b) (i) Add the missing value to Table 6. Explain why you chose this value. [3 marks] ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ 6 (b) (ii) During this investigation the spring exceeded its limit of proportionality. Suggest a value of force at which this happened. Give a reason for your answer. [2 marks] Force = ................................. N Reason .............................................................................................................................. ............................................................................................................................................ ............................................................................................................................................ Question 6 continues on the next page Turn over  (27) G/Jun14/8403/2  28 Do not write outside the box 6 (c) In a third investigation the student: ● suspended a 100 g mass from a spring ● pulled the mass down as shown in Figure 16 ● released the mass so that it oscillated up and down ● measured the time for 10 complete oscillations of the mass ● repeated for masses of 200 g, 300 g and 400 g. Figure 16 Mass Her results are shown in Table 7. Table 7 Time for 10 complete oscillations in seconds Mass in g Test 1 Test 2 Test 3 Mean 100 4.34 5.20 4.32 4.6 200 5.93 5.99 5.86 5.9 300 7.01 7.12 7.08 7.1 400 8.23 8.22 8.25 8.2 (28) G/Jun14/8403/2  29 Do not write outside the box 6 (c) (i) Before the mass is released, the spring stores energy. What type of energy does the spring store? Tick () one box. [1 mark] Tick () Elastic potential energy Gravitational potential energy Kinetic energy 6 (c) (ii) The value of time for the 100 g mass in Test 2 is anomalous. Suggest two likely causes of this anomalous result. Tick () two boxes. [2 marks] Tick () Misread stopwatch Pulled the mass down too far Timed half oscillations, not complete oscillations Timed too few complete oscillations Timed too many complete oscillations 6 (c) (iii) Calculate the correct mean value of time for the 100 g mass in Table 7. [1 mark] ............................................................................................................................................ ............................................................................................................................................ Mean value = .................................... s Question 6 continues on the next page Turn over  (29) G/Jun14/8403/2  30 Do not write outside the box 6 (c) (iv) Although the raw data in Table 7 is given to 3 significant figures, the mean values are correctly given to 2 significant figures. Suggest why. [2 marks] ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ 6 (c) (v) The student wanted to plot her results on a graph. She thought that four sets of results were not enough. What extra equipment would she need to get more results? [2 marks] ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ............................................................................................................................................ ____ 17 END OF QUESTIONS (30) G/Jun14/8403/2  31 Do not write outside the box There are no questions printed on this page DO NOT WRITE ON THIS PAGE ANSWER IN THE SPACES PROVIDED (31) G/Jun14/8403/2  32 Do not write outside the box There are no questions printed on this page DO NOT WRITE ON THIS PAGE ANSWER IN THE SPACES PROVIDED Acknowledgement of copyright-holders and publishers Permission to reproduce all copyright material has been applied for. In some cases, efforts to contact copyright-holders have been unsuccessful and AQA will be happy to rectify any omissions of acknowledgements in future papers if notified. Question 1 Oscilloscope connected to a microphone with a tuning fork © Alamy Question 3 Photograph of a lead-lined wooden box © David McKean Copyright © 2014 AQA and its licensors. All rights reserved. (32) G/Jun14/8403/2