Half Term PHYSICS Paper 2 FOUNDATION. What is the resultant force acting on the object?

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1 Half Term PHYSICS Paper 2 FOUNDATION Name:.. Attempt ALL Questions and bring the completed test to your first Physics lesson after the holiday. Mark /75 Q.(a) The diagram shows two forces acting on an object. What is the resultant force acting on the object? Tick ( ) one box. 8 N to the right 8 N to the left 4 N to the right 4 N to the left () BASE jumpers jump from very high buildings and mountains for sport. The diagram shows the forces acting on a BASE jumper in flight. The BASE jumper is wearing a wingsuit. (i) Draw a ring around the correct answer in the box to complete each sentence. smaller than The BASE jumper accelerates forwards when force A is equal to force B. bigger than Page

2 smaller than The BASE jumper falls with a constant speed when force C is equal to force D. bigger than (ii) To land safely the BASE jumper opens a parachute. What effect does opening the parachute have on the speed of the falling BASE jumper?... Give a reason for your answer (Total 5 marks) Q2.A powerlifter lifts a 80 kg bar from the floor to above his head. Page 2

3 (a) Use the equation in the box to calculate the weight of the bar. weight = mass gravitational field strength gravitational field strength = 0 N/kg Show clearly how you work out your answer. Weight =... N The powerlifter uses a constant force to lift the bar a distance of 2. m. Use the equation in the box to calculate the work done by the powerlifter. work done = force applied distance moved in direction of force Show clearly how you work out your answer and give the unit. Choose the unit from the list below. joule newton watt Work done =...J At the end of the lift, the powerlifter holds the bar stationary, above his head, for two seconds. How much work does the powerlifter do on the bar during these two seconds? Draw a ring around your answer Give a reason for your answer. (Total 6 marks) Page 3

4 Q3.Small water waves are created in a ripple tank by a wooden bar. The wooden bar vibrates up and down hitting the surface of the water. The figure below shows a cross-section of the ripple tank and water. (a) Which letter shows the amplitude of a water wave? Tick one box. J K L () The speed of the wooden bar is changed so that the bar hits the water fewer times each second. What happens to the frequency of the waves produced? Tick one box. Increases Does not change Decreases () Describe how the wavelength of the water waves in a ripple tank can be measured accurately Page 4

5 (d) The speed of a wave is calculated using the following equation. wave speed = frequency wavelength The water waves in a ripple tank have a wavelength of.2 cm and a frequency of 8.5 Hz. How does the speed of these water waves compare to the typical speed of a person walking? (4) (Total 8 marks) Q4.(a) Use the correct answer from the box to complete the sentence. balancing stretching turning A moment is the... effect of a force. () Figure shows how a lever can be used to lift a heavy rock. Calculate the moment of the weight of the rock about point P. Moment =... newton metres Page 5

6 Figure 2 shows three positions on the lever, A, B and C, where the person could have applied a force to lift the rock. Which position, A, B or C, needs the smallest force to lift the rock? Draw a ring around the correct answer. A B C Give the reason for your answer. (Total 5 marks) Q5.The diagram shows a demonstration carried out by a teacher. When the switch is closed, there is a current of 2 A through the wire. The wire experiences a force and moves. Page 6

7 (a) Use the correct word from the box to complete the sentence. generator motor transformer The demonstration shows the... effect. () State two changes that the teacher could make to the demonstration, each of which would increase the force on the wire. The teacher does not touch the wire State one change that the teacher could make to the demonstration to change the direction of the force on the wire. () (d) With the switch closed, the teacher changes the position of the wire so that the force on the wire is zero. What is the position of the wire? Tick ( ) one box. The wire is at 90 to the direction of the magnetic field. The wire is at 45 to the direction of the magnetic field. The wire is parallel to the direction of the magnetic field. () (Total 5 marks) Page 7

8 Q6.The figure below shows a coil and a magnet. An ammeter is connected to the coil. The ammeter has a centre zero scale, so that values of current going in either direction through the coil can be measured. (a) A teacher moves the magnet slowly towards the coil. Explain why there is a reading on the ammeter. (4) Page 8

9 The table below shows some other actions taken by the teacher. Complete the table to show the effect of each action on the ammeter reading. Action taken by teacher What happens to the ammeter reading? Holds the magnet stationary and moves the coil slowly towards the magnet Holds the magnet stationary within the coil Moves the magnet quickly towards the coil Reverses the magnet and moves it slowly towards the coil (4) The magnet moves so that there is a steady reading of 0.05 A on the ammeter for 6 seconds. Calculate the charge that flows through the coil during the 6 seconds. Give the unit. Charge =... (3) (Total marks) Q7.Infrared and microwaves are two types of electromagnetic radiation. The diagram below shows the positions of the two types of radiation within part of the electromagnetic spectrum. (a) Name one type of electromagnetic radiation which has more energy than infrared.... () Page 9

10 Use the correct answer from the box to complete each sentence. Each answer may be used once, more than once or not at all. greater than less than the same as The wavelength of infrared is... the wavelength of microwaves. The frequency of microwaves is... the frequency of infrared. The speed of microwaves in a vacuum is... the speed of infrared in a vacuum. (3) (Total 4 marks) Q8. (a) A person takes their dog for a walk. The graph shows how the distance from their home changes with time. Which part of the graph, A, B, C or D, shows them walking the fastest? Write your answer in the box. Give the reason for your answer. During the walk, both the speed and the velocity of the person and the dog change. How is velocity different from speed? () (Total 3 marks) Page 0

11 Q9.Figure shows the structure of a traditional transformer. Figure (a) There is an alternating current in the primary coil of the transformer. State what is produced in the iron core A transformer has only one turn of wire on the secondary coil. The potential difference across the secondary coil is.5 V The potential difference across the primary coil is 230 V Use the Physics Equation Sheet calculate the number of turns on the primary coil Number of turns on the primary coil =... In most transformers, the power output is less than the power input. State why () Page

12 (d) Two students investigated how magnets can be used to produce a potential difference. The students held a coil of wire above a magnet. The students quickly lowered the coil so that the magnet was inside the coil, as shown in Figure 2. Figure 2 The students recorded the maximum potential difference for coils with different numbers of turns of wire. The results are shown in the table. Number of turns of wire in the coil Maximum potential difference in volts Results from student Results from student (i) State the resolution of the voltmeter. Give one reason why the resolution of the voltmeter is suitable for this investigation. Resolution... Reason (ii) The two students used exactly the same equipment to carry out their investigations. Both students recorded their results correctly. Give the reason why student 2 got different results from student () Page 2

13 (iii) The students decided that even though the results were different, there was no need to repeat the investigation. How do the results show that the investigation is reproducible? () (iv) State the name of the process which causes the potential difference to be produced in this investigation.... () (Total 0 marks) Q0.The diagram shows a boat pulling a water skier. (a) The arrow represents the force on the water produced by the engine propeller. This force causes the boat to move. Explain why. The boat accelerates at a constant rate in a straight line. This causes the velocity of the water skier to increase from 4.0 m/s to 6.0 m/s in 8.0 seconds. (i) Calculate the acceleration of the water skier Acceleration =...m/s/s Page 3

14 (ii) The water skier has a mass of 68 kg. Calculate the resultant force acting on the water skier while accelerating Resultant force =... N (iii) Draw a ring around the correct answer to complete the sentence. The force from the boat pulling the water skier forwards less than will be the same as the answer to part (ii). greater than Give the reason for your answer (Total 8 marks) Q. Infrared and microwaves are two types of electromagnetic radiation. (a) State one example of the use of each type of radiation for communication. Infrared:... Microwaves:... Some of the properties of infrared and microwaves are the same. State two of these properties (Total 4 marks) Page 4

15 Q2. The data given in the table below was obtained from an investigation into the refraction of light at an air to glass boundary. Angle of incidence Angle of refraction Describe an investigation a student could complete in order to obtain similar data to that given in the table above. Your answer should consider any cause of inaccuracy in the data. A labelled diagram may be drawn as part of your answer (Total 6 marks) Page 5

16 Half Term PHYSICS Paper 2 FOUNDATION MS M.(a) 4 N to the right (i) bigger than equal to (ii) reduces it increases air resistance / drag / force C accept parachute has large(r) (surface) area [5] M2.(a) 800 (N) allow mark for correct substitution ie 80 0 provided no further steps shown or their (a) 2. correctly calculated allow mark for correct substitution ie 800 or their (a) 2. provided no further steps shown 2 0 reason does not score if 0 not chosen work is only done when a force makes an object move accept distance moved is zero accept no energy transfer (to the bar) accept the bar is not moving/is stationary 'it' refers to the bar/weights [6] M3.(a) K Decreases use a metre rule / 30 cm ruler to measure across 0 (projected) waves Page 6

17 accept any practical number of waves number for 0 and then divide by 0 (d).2 cm = 0.02 m = 0.22 (m / s) allow 0.22 with no working shown for 2 marks typical walking speed =.5m / s accept any value e.g. in the range 0.7 to 2.0 m / s so the water waves are slower (than a typical walking speed) this cannot score on its own [8] M4.(a) turning 420 allow mark for correct substitution, ie provided no subsequent step shown 2 A reason only scores if A is chosen any one correct reason: the force is furthest away (from the pivot) accept distance (from the pivot) is the greatest accept it is further away (from the pivot) accept furthest away from the rock [5] M5.(a) motor increase the strength of the magnetic field accept use a stronger magnet use a larger / bigger magnet is insufficient do not accept move magnets closer increase the (size of the) current Page 7

18 accept use a current greater than 2 (A) accept increase the p.d. / voltage (of the power supply) increase the power supply is insufficient any one from: (reverse the) direction of the current accept swap the wires at the power supply connections swap the wires around is insufficient (change the) direction of the magnetic field accept turn the magnet around do not accept use an a.c. supply (d) The wire is parallel to the direction of the magnetic field. [5] M6.(a) Any 4 of: there is a magnetic field (around the magnet) (this magnetic field) changes / moves and cuts through coil accept links with coil so a p.d. induced across coil the coil forms a complete circuit so a current (is induced) ammeter reading does not change must be in this order accept ammeter has a small reading / shows a current zero greater than before accept a large(r) reading same as originally but in the opposite direction accept a small reading in the opposite direction 0.30 allow mark for correct substitution, ie 0.05 = Q / 6 Page 8 2

19 C / coulomb allow A s [] M7.(a) any one from: (visible) light UV / ultra violet X-ray gamma / γ-ray less than less than the same as [4] M8. (a) B reason only scores if B is chosen gradient / slope is the steepest / steeper answers must be comparative accept steepest line ignore greatest speed (velocity includes) direction it refers to velocity [3] M9.(a) a magnetic field accept electromagnetic field heat is insufficient that is alternating / changing 20 allow mark for correct substitution, ie provided no subsequent step 2 (most) transformers are not 00% efficient allow energy / power is lost to the surroundings Page 9

20 (d) (i) 0.0 (V) allow energy / power is lost as heat / sound power is lost is insufficient because there is a change in p.d. each time (the number of turns changes) allow because all the results (to 2 decimal places) are different accept if results were to decimal place, there might not be a difference (ii) student 2 moved the coil more slowly (than student ) accept student 2 moved the coil at a different speed to student do not accept student 2 moved the coil faster (than student ) (iii) both sets of results show the same pattern accept trend for pattern results are similar is insufficient results follow a pattern is insufficient (iv) (electromagnetic) induction accept it is induced do not accept electric / magnetic induction [0] M0.(a) (produces) a force from water on the boat in the forward direction accept in the opposite direction this must refer to the direction of the force not simply the boat moves forwards an answer produces an (equal and) opposite force gains mark (i).5 allow mark for correct substitution, ie provided no subsequent step shown ignore sign or 2 (ii) 02ortheir (i) 68 correctly calculated Page 20

21 (iii) allow mark for correct substitution, ie.5 68 or their (i) 68 provided no subsequent step shown greater than reason only scores if greater than chosen 2 need to overcome resistance forces accept named resistance force accept resistance forces act (on the water skier) do not accept gravity [8] M.(a) use of infrared: remote controls fibre optic (communications) use of microwaves: mobile/cell phones accept mobiles accept phone signals satellite (communications/tv) wi-fi Bluetooth any two from same speed or travel at the speed of light (in a vacuum) transverse accept a full description of a transverse wave transfer energy (from one place to another) can be reflected can be refracted can be diffracted can be absorbed / transmitted can travel through a vacuum/space can be polarised travels in straight lines is insufficient 2 [4] Page 2

22 M2.Level 3 (5 6 marks): A detailed and coherent plan covering all the major steps is provided. The steps in the method are logically ordered. The method would lead to the production of valid results. A source of inaccuracy is provided. Level 2 (3 4 marks): The bulk of a method is described with mostly relevant detail. The method may not be in a completely logical sequence and may be missing some detail. Level ( 2 marks): Simple statements are made. The response may lack a logical structure and would not lead to the production of valid results. 0 marks: No relevant content. Indicative content place a glass block on a piece of paper draw around the glass block and then remove from the paper draw a line at 90 to one side of the block (the normal) use a protractor to measure and then draw a line at an angle of 20 to the normal replace the glass block using a ray box and slit point the ray of light down the drawn line mark the ray of light emerging from the block remove the block and draw in the refracted ray measure the angle of refraction with a protractor repeat the procedure for a range of values of the angle of incidence possible source of inaccuracy the width of the light ray which makes it difficult to judge where the centre of the ray is [6] Page 22

23 Half Term PHYSICS Paper 2 FOUNDATION E.(a) Just under two thirds of students answered this correctly. (i) Approximately two thirds of students gained both marks. (ii) Most students correctly stated that the BASE jumper slowed down. The reason was not well expressed. Many students thought that an increase in upthrust was sufficient to slow the BASE jumper whilst others said that the parachute slows the acceleration, implying that the BASE jumper continues to accelerate. E2.(a) Nearly 80% of students scored both marks. About 40% of students completed the calculation correctly with approximately 26% of these students being able to identify the correct unit. The most common error was to use the mass of the bar rather than the weight of the bar. Considering how often students are asked to give a unit it is surprising how few are able to recall the more common ones. This was poorly answered. The majority of students gave answers other than zero. Those students choosing zero were often unable to give the correct reason for choosing this value. E4.(a) More than half of the students scored this mark. Almost all of the students were able to substitute into the correct equation and to calculate the moment of the weight of the rock. The correct position was given by about three quarters of students with half of the students scoring both marks. Many students who failed to score the second mark wrote about position A giving more leverage, but failed to state that this was because position A was furthest from the pivot. E5.(a) Nearly three quarters of the students scored this mark. (d) Many students who did not score either mark were along the right lines and mentioned both current and the strength of the magnet, but did not state that these needed to be increased. A number of students gave vague answers such as increase the power supply rather than indicating that an increase in potential difference or current was needed. Only one fifth of the students scored both marks, with a further third of the students scoring one mark. Just under half of the students scored this mark. A large proportion of the students who failed to score this mark suggested using an a.c. supply. Some students also gave answers in terms of changing the cotton thread. Approximately three quarters of the students scored this mark. E6.(a) This question was quite well done, with some almost text-book answers. Although only a small minority scored all six marks, around three-quarters of students scored at least two marks, usually for mentioning the magnetic field and the current produced. There were, however, a small number of confused answers relating to the motor effect. Having answered the question, a significant number of students went on to explain what would happen if the magnet were withdrawn / moved faster / moved slower etc. Page 23

24 Half of the students scored at least two of the four marks. A common mistake was not relating the actions to the original movement of the magnet, so that comparisons of size and direction of current were not made. This was answered well, with nearly all students achieving both marks for the calculation, and nearly two-thirds scoring the mark for the correct unit. E7.(a) Over two thirds of students scored this mark. One of the most common correct responses was visible light; quite a few went to the very end of the EM spectrum and stated gamma rays, which was also creditworthy. Just under half of students scored 2 marks, few scored all 3 marks. Many students incorrectly thought that each response should only be used once, having not read the question carefully enough. E8. (a) Most students correctly chose B. Most students then realised that the gradient was the important feature of the graph to consider. Answers needed to be comparative so steep line was not credited. Attempts at describing a gradient were often unsuccessful as no comparison with other sections of the graph was made. It was disappointing that only two fifths of students could give the difference between velocity and speed. Many students gave velocity as the change of speed or the change of direction. E9.Foundation (a) Less than a quarter of students realised that a magnetic field was produced, whereas other students thought that a current or p.d. was produced in the iron core. It was not common for students to gain the mark for realising that the magnetic field produced would be changing. This calculation was handled well by students, with just under three quarters gaining both marks. Many students confused the loss of power with it being a step-down transformer. The most common way of students gaining the mark was for noting that energy is transferred by heating. Just under one fifth of students answered correctly. (d) (i) Few students were able to correctly identify the resolution, although many more students were along the right lines, with an answer of 2 decimal places occurring regularly. The reason for this being appropriate was less well answered with many students answering how they knew that this was the resolution, rather than answering the question of why this was a suitable resolution for this experiment. Just under a fifth of students gained marks on this question. (ii) (iii) (iv) Just under one tenth of students correctly stated why the results were different. Slightly more than a tenth of students answered this question correctly. Many students thought that a lack of anomalous results made the experiment reproducible, or just the fact that two students had carried out the experiment made it reproducible. Many students just quoted numbers given in the table. Induction was clearly something which students struggled with, and the question was only attempted by about two thirds of students. Only a few Page 24

25 students knew the name of the process. (e) Just over half of students were able to suggest an advantage of the transformer. It was not uncommon for those who got the question wrong to have just repeated the stem of the question. Higher (a) Approximately two thirds of students realised that a magnetic field was produced, whereas other students thought that a current or p.d. was produced in the iron core. Only about a quarter of students realised that the magnetic field produced would be changing. This calculation was handled well by students, with the vast majority gaining both marks. Many students confused the loss of power with it being a step-down transformer. The most common way of students gaining the mark was for noting that energy is transferred by heating. Just under four tenths of students answered correctly. (d) (i) Many students struggled to identify the correct resolution, although some were along the right lines, with answers of 2 decimal places or 0.00 occurring regularly. The reason for it being appropriate was less well done with many students answering how they knew that this was the resolution, rather than answering the question of why this was a suitable resolution for this experiment. Less than half of students gained marks on this question. (ii) (iii) (iv) About a third of students answered this question correctly. Many students stated that part of the equipment being used was different, despite the stem of the question clearly stating that the two students used exactly the same equipment. Just over a third of students answered this question correctly. Many students thought that similar results made it reproducible, rather than there being a similar pattern in results. Fewer than half the students stated the correct process. (e) Over two thirds of students suggested a correct advantage. Unrewarded responses frequently just repeated the stem of the question. E0.(a) This was very poorly answered with few students scoring any marks. The students had great difficulty in explaining the forces involved to move the boat forward, very few wrote that the water provided a force on the boat. Those that did usually failed to give a direction to the force. (i) The calculation was well done with nearly three quarters of the students giving the correct numerical answer. However few students were able to give the correct unit. A significant minority of students incorrectly obtained an answer of 5.5. This was caused by incorrect use of the calculator when working out a substitution written as (ii) (iii) Again this calculation was well done with the vast majority of students giving a correct answer. Only half of the students gave the correct answer with very few students being able to give a correct reason for their choice. Answers were generally in Page 25

26 terms of a greater force is needed as the skier is accelerating. E.(a) Two fifths of students scored 2 marks, while one third of students scored mark. The vast majority of students scored 2 marks for 'remote controls' and 'mobile phones'. A reasonable number of students misread the question and wrote down any use of infrared (conventional oven) and microwave (the microwave) which were insufficient for communications. 'Phone' by itself was insufficient, but 'phone signals' was creditworthy, as was 'sending text messages'. While some mobile phones do have infrared ports, this was insufficient for a use of infrared as not all mobile phones have this facility. Satellite (communications) was another common answer seen for use of microwaves. TV alone was insufficient. Other insufficient answers included: key fobs for remote locking of cars, computer peripherals and walkie talkies, all of which typically use radio frequencies. A quarter of students scored 2 marks, while a fifth of students scored only mark. Students should be reminded of the list principle: if two answers are required, only give two answers, otherwise incorrect answers can negate correct answers. One student stated 5 properties that were the same for both waves; fortunately for the student they were all correct. Insufficient responses included 'can't be seen with the human eye', 'not harmful', 'can heat food', 'used for communication'. Incorrect responses included 'same amplitude / frequency / wavelength'. A student who stated 'travel through a vacuum at the speed of light' and didn't write anything on the second line would score 2 marks for their single statement. Page 26