Fizika | Középiskola » Fizika angol nyelven középszintű írásbeli érettségi vizsga megoldással, 2012

ÉRETTSÉGI VIZSGA 2012. május 17 Név: . osztály: FIZIKA ANGOL NYELVEN KÖZÉPSZINTŰ ÍRÁSBELI VIZSGA 2012. május 17 8:00 Az írásbeli vizsga időtartama: 120 perc Fizika angol nyelven Pótlapok száma Tisztázati Piszkozati NEMZETI ERŐFORRÁS MINISZTÉRIUM középszint írásbeli vizsga 1121 Fizika angol nyelven középszint Név: . osztály: Instructions for the examinee The time allowed for the examination is 120 minutes. Read the instructions for the problems very carefully and use your time wisely. You may solve the problems in arbitrary order. Allowable materials: pocket calculator, data tables. Should the space provided for the solution of a problem be insufficient, you may continue the solution on one of the empty sheets at the end of the examination. Please indicate the number of the problem on the sheet. Please indicate here which of the two problems 3/A and 3/B you have chosen (that is, which one you would like evaluated): 3 írásbeli vizsga 1121 2

/ 16 2012. május 17 Fizika angol nyelven középszint Név: . osztály: PART ONE Precisely one of the possible solutions for each of the following questions is correct. Write the corresponding letter in the white square on the right! (Check your answer with calculations if necessary.) 1. Since the year 2006 astronomers no longer classify Pluto as a planet, it has been declared a dwarf planet. Which is the outermost planet of our Solar system now? A) B) C) Saturn. Uranus. Neptune. 2 points 2. How does a raindrop fall? We know that besides gravitation, air drag also exerts a force on it. A) B) C) It moves with a constant acceleration, as both the gravitational force and the force due to air drag are constant, but the later one is smaller. It starts with an accelerating motion, but its speed becomes practically constant after a while, because the force due to air drag increases with speed. In the beginning its speed increases, but after a while it decreases again as the

force due to air drag becomes greater than the gravitational force. 2 points 3. Water is often employed as a coolant because it flows easily Which other property of water is favorable from this point of view? A) B) C) Water is a good coolant because its specific heat is large. Water is a good coolant because it is a good conductor of heat. Water is a good coolant because its latent heat of fusion is high. 2 points írásbeli vizsga 1121 3 / 16 2012. május 17 Név: . osztály: Fizika angol nyelven középszint 4. We fix point charges of magnitude Q = 1 µC at the three vertices of a right-angled isosceles triangle. As it can be seen on the figure, one charge is negative, the other two are positive. What is the direction of the electrostatic force exerted on the charge at the right-angled vertex of the triangle by the other two charges? N E W S A) B) C) The electrostatic force points Northwest. The electrostatic force points Northeast. The electrostatic force is zero,

because the sum of the other two charges is zero. 2 points 5. Each of the two position-time graphs below depict the motion of a point-like body with constant speed. Which graph depicts the motion of the faster body? x(m) 8 x(m) 4 4 2 4 A) B) C) 8 t(s) 4 8 t(s) The motion of the faster body is depicted by the graph on the right. The two bodies move with the same speed. The motion of the faster body is depicted by the graph on the left. 2 points 6. We inflate a balloon What can we say about the air pressure inside the balloon? A) B) C) It is greater than the outside pressure. It is equal to the outside pressure. It is smaller than the outside pressure. 2 points írásbeli vizsga 1121 4 / 16 2012. május 17 Fizika angol nyelven középszint Név: . osztály: 7. We hold a massive pole in equilibrium with a rope in two different ways. The pole can rotate without friction around the axle that is perpendicular to the plane of the paper. In which case will the force in

the rope be greater? (The pole encloses an angle of about 75o with the ground.) A) B) C) In the case depicted in figure A). In the case depicted in figure B). The force in the rope will be the same in both cases. 2 points 8. A flat mirror forms a virtual image How does the image size change when the object distance is doubled? A) B) C) The image size is also doubled. The image size remains unchanged. The image size is halved. 2 points 9. In the circuit depicted on the figure the voltage of the battery is U0 = 10 V, while the resistance of the two resistors is the same. What is the voltage between the two points A and B when the switch is in an open position? A) B) C) A B R R U0 UAB = 10 V. UAB = 5 V. UAB = 0 V. 2 points írásbeli vizsga 1121 5 / 16 2012. május 17 Fizika angol nyelven középszint Név: . osztály: 10. A spring with a spring constant D2 = 400 N/m is attached to the end of another spring whose spring constant is D1 = 200 N/m such that the two

springs lie along a straight line. The free ends of springs are pulled apart Which of the two springs will be stretched more? (The springs are at rest!) A) B) C) The spring with spring constant D1 = 200 N/m will be stretched more. The spring with spring constant D2 = 400 N/m will be stretched more. The two springs will stretch by the same amount. 2 points 11. A metal is illuminated with 21 eV photons This causes electrons to be emitted with a maximum energy of 0.7 eV With what photon energy should we illuminate this metal in order to have electrons emitted with a maximum energy of 1.4 eV? A) B) C) With 4.2 eV photon energy With 3.6 eV photon energy With 2.8 eV photon energy 2 points 12. The shadow of a pole points north at solar noon In which direction will it move in the afternoon? A) B) C) It will move in a clockwise direction. It will move in a counterclockwise direction. It will not move, only become longer. 2 points 13. We use a 04 m focal length concave mirror to image a

candle located 3 m from the mirror on a screen. How does the image distance change if we move the candle closer to the mirror? A) B) C) The image distance decreases. The image distance increases. The image distance does not change. 2 points írásbeli vizsga 1121 6 / 16 2012. május 17 Fizika angol nyelven középszint Név: . osztály: 14. We have two samples that contain alpha-emitting radioactive isotopes with different half-lives. At a given moment, both samples contain the same number of radioactive nuclei. At this moment we switch on two GM counters to detect the alpha particles emitted from each of the samples. From which sample do we detect an alpha particle first? A) B) C) From the sample whose half-life is smaller. From the sample whose half-life is greater. It is impossible to say which sample will emit an alpha particle sooner. 2 points 15. A rock is at rest on the ground Naturally, a force acts upon it due to Earths gravity What can we say about the reaction

force of this gravitational force? A) B) C) The reaction force of the gravitational force is just the force by which the rock attracts the Earth. The reaction force of the gravitational force is the weight of the rock. The reaction force of the gravitational force is the force exerted on the rock by the ground which supports it. 2 points 16. We have two gas containers, one with a volume of 200 liters, and one with a volume of 400 liters. Both contain 5 kg of carbon dioxide gas We have to cool this gas – which can be assumed to be an ideal gas – from 20 oC to -10 oC in both containers. In which case do we have to extract more heat from the gas to achieve this? A) B) C) In the case of the 200 liter container, as the gas pressure there is greater. In the case of the 400 liter container, as the gas pressure there is smaller. We have to extract the same amount of heat in both cases. 2 points 17. We would not be able to observe shooting stars while standing on the Moon Why is that

so? A) B) C) Because the Moon does not possess an atmosphere. Because gravity on Moon’s surface is smaller than that of the Earth. Because light cannot propagate through vacuum. 2 points írásbeli vizsga 1121 7 / 16 2012. május 17 Fizika angol nyelven középszint Név: . osztály: 18. In the past, one cent coins in the United States of America were made purely of copper. Nowadays they are made of zinc, but are covered with copper, so that they look exactly the same as the old ones. We have two one cent coins in our hands, an old one and a new one, which look totally identical. Which property of the coins can we use to differentiate between them? A) B) C) The mass of the old coin is certainly different from that of the new coin. The old coin certainly looks more worn than the new one. If the two coins look totally identical, we cannot differentiate between them. 2 points 19. We break a magnetic bar in two and turn one half of it parallel to the other half without

lifting it from the table as shown on the figure. What kind of magnetic interaction will there be between the two pieces? A) B) C) An attractive interaction. A repulsive interaction. There will not be any magnetic interaction between them. 2 points 20. Did Leó Szilárd have a role in developing the nuclear reactor? A) B) C) No, he could not have had a role, as he was kept away from the research of atomic energy all along because he was a suspicious foreigner. No, he did not have a role. He obtained fame later when curing his own cancer with radiotherapy. Yes he did, which is illustrated by the fact that for the patent of the nuclear reactor that he shared with Enrico Fermi the government of the United States paid him one dollar. 2 points írásbeli vizsga 1121 8 / 16 2012. május 17 Fizika angol nyelven középszint Név: . osztály: PART TWO Solve the following problems. Justify your statements using calculations, diagrams or explanations, depending on the nature of the

questions. Make sure that the notations you use are unambiguous. 1. An experiment to measure reaction time is depicted in the figure. In this experiment, we hold a ruler by the upper end, while our companion holds his hand with two fingers open at the lower end of the hanging ruler at the 0 cm mark, ready to catch it. Suddenly we release the ruler. Upon noticing this, our companion tries to catch the ruler by closing his fingers. He is not allowed to move his hand vertically! One can read the mark of the ruler where our companion caught it. It is then possible to determine the time elapsed between the release of the ruler and the closing of the fingers, i.e the reaction time of our companion can be measured. We test three of our companions this way a) b) c) The reaction time of our first companion is 0.15 s Where will he catch the ruler? Our second companion caught the ruler at the 20 cm mark. What is his reaction time? How fast was the ruler moving when he caught it? The reaction

time of our third companion is twice that of the first one. Will he catch the ruler? If so, where? g = 10 m/s2, the length of the ruler is L = 30 cm. írásbeli vizsga 1121 9 / 16 2012. május 17 Fizika angol nyelven középszint Név: . osztály: a) b) c) Total 4 points 6 points 3 points írásbeli vizsga 1121 10 / 16 13 points 2012. május 17 Fizika angol nyelven középszint 2. Név: . osztály: We pour 200 grams of 10 oC milk into a 20 oC nursing bottle weighting 300 grams and insert it into an electric food warmer. The warmer heats the bottle and the milk to 38 oC. a) b) c) How much heat did the warmer transfer to the milk and the bottle together? How much time was required for the heating, if the warmers net power is 90 W? What is the amount of heat lost during the heating if the warmers nominal power is 120 W? Data: the specific heat of milk is cmilk = 4000 c glass = 840 J , the specific heat of glass is kg ⋅ °C J kg ⋅ °C a) b) c) Total 8

points 5 points 4 points írásbeli vizsga 1121 11 / 16 17 points 2012. május 17 Fizika angol nyelven középszint Név: . osztály: You need to solve only one of the two problems 3/A and 3/B. Indicate your choice on the inside of the front cover. 3/A In the course of the photoelectric effect, photons eject electrons from a silver plate. The table below contains the energy of the incident photons and the kinetic energy of the emitted electrons. (This latter has been determined by measuring voltage) One piece of data is missing from the table. photon energy - (eV) electron energy - (eV) a) b) c) d) 5.12 0.41 5.88 1.12 1.52 6.92 2.17 7.55 2.77 7.92 3.20 Plot the kinetic energy of the emitted electrons as a function of the incident photon energy. Using the data above, determine the work function of silver. What is the greatest light wavelength at which the ejection of electrons still happens? Determine the piece of data missing from the table using calculations or

using the graph. (h = 6.67 · 10-34 Js, 1 eV = 16 · 10-19 J, c = 3 ·108 m/s) írásbeli vizsga 1121 12 / 16 2012. május 17 Fizika angol nyelven középszint Név: . osztály: a) b) c) d) Total 6 points 4 points 8 points 2 points írásbeli vizsga 1121 13 / 16 20 points 2012. május 17 Fizika angol nyelven középszint Név: . osztály: 3/B Electric energy is transported via high tension power lines without insulation. We can often see birds perching on these cables without any harm coming to them. However we also know, that around 40 000 birds are killed a year in Hungary due to electric shock. Most often, the accidents happen on the poles of the 20 kV cables of the energy distribution network. The figures depict the two positions which lead to the electrocution of the birds most often. Fig. 1 2. Fig. 2 Fig. 3 Fig 4. Fig. 5 Answer the following questions based on the introduction and the figures. a) Why is a bird perching on the cable not

electrocuted? (Fig.1) b) Why is a bird perching on the grounded metal component of the pole electrocuted when it touches the cable? (Fig. 2) c) Why is it fatal if a bird touches two cables at once? (Fig 3.) d) Why does it happen much more rarely that a bird touches two cables at once on the taller, higher voltage poles (Fig. 4) than on the smaller, 20 kV poles (Fig 5)? e) Give two suggestions for measures that can be taken to avoid the electrocution of birds. írásbeli vizsga 1121 14 / 16 2012. május 17 Név: . osztály: Fizika angol nyelven középszint a) b) c) d) e) Total 5 points 2 points 2 points 3 points 8 points írásbeli vizsga 1121 15 / 16 20 points 2012. május 17 Fizika angol nyelven középszint Név: . osztály: To be filled out by the examiner evaluating the paper! maximum score I. Multiple choice questions II. Complex problems score attained 40 50 Total score of the written exam 90 examiner Date: .

Score attained rounded to the nearest integer (elért pontszám egész számra kerekítve) Integer score entered in the program (programba beírt egész pontszám) I. Multiple choice questions (Feleletválasztós kérdéssor) II. Complex problems (Összetett feladatok) examiner (javító tanár) notary (jegyző) Date (Dátum): . Date (Dátum): írásbeli vizsga 1121 16 / 16 2012. május 17 ÉRETTSÉGI VIZSGA 2012. május 17 Fizika angol nyelven középszint Javítási-értékelési útmutató 1121 FIZIKA ANGOL NYELVEN KÖZÉPSZINTŰ ÍRÁSBELI ÉRETTSÉGI VIZSGA JAVÍTÁSI-ÉRTÉKELÉSI ÚTMUTATÓ NEMZETI ERŐFORRÁS MINISZTÉRIUM Fizika angol nyelven középszint Javítási-értékelési útmutató The examination papers should be evaluated and graded clearly, according to the instructions of the evaluation guide. Markings should be in red ink, using the conventional notations FIRST PART For the multiple choice

questions, the two points may only be awarded for the correct answer given in the evaluation guide. Enter the score (0 or 2) in the gray rectangle next to the question as well as the table for total scores at the end of the exam paper. SECOND PART The individual scores shown in the evaluation guide may not be broken up unless explicitly indicated. The sentences printed in italics in the evaluation guide define the steps necessary for the solution. The scores indicated here may be awarded if the action or operation described by the text in italics can be clearly identified in the work of the examinee and is basically correct and complete. Wherever the action can be broken down into smaller steps, partial scores are indicated beside each line of the expected solution. The „expected solution” is not necessarily complete; its purpose is to indicate the depth of detail required of the examinee when writing the solution and the type of solution expected. Comments in brackets that follow

provide further guidance on the evaluation of possible errors, differences or incomplete answers. Correct answers that differ from the reasoning of the one (ones) given in the evaluation guide are also acceptable. The lines in italics provide guidance in allocating scores, eg how much of the full score may be awarded for correct interpretation of the question, for stating relationships, for calculations, etc. Should the examinee combine some steps, or carry on calculations algebraically, he/she may skip the calculation of intermediate results shown in the evaluation guide. If these intermediate results are not being explicitly asked for in the original problem, the scores indicated for them should be awarded if the reasoning is otherwise correct. The purpose of indicating scores for intermediate results is to make the evaluation of incomplete solutions easier. For errors that do not affect the correctness of reasoning (miscalculations, clerical errors, conversion errors, etc.) deduce

points only once Should the examinee write more than one solutions, or display multiple attempts at solving the problem, and does not indicate clearly which one of those he/she wants evaluated, the last one should be considered (i.e the one at the bottom of the page if there is nothing to indicate otherwise). If the solution contains a mixture of two different trains of thought, the elements of only one of them should be evaluated: that one which is more favorable for the examinee. The lack of units during calculation should not be considered a mistake – unless it causes an error. However, the results questioned by the problem are acceptable only with proper units. Graphs, diagrams and notations are acceptable only if they are unambiguous (it must be clear what the graphs show, markings should be in place, unconventional notations must be explained, etc.) The lack of units on the axis labels of graphs should not be considered a mistake however, if the units are otherwise obvious (e.g

quantities given in a table must be plotted, all with the same units). If, in case of problem 3 the examinee does not indicate his/her choice, the procedure described in the exam description should be followed. Following the evaluation, the appropriate scores should be entered into the tables at the bottom of each page. írásbeli vizsga 1121 2/8 2012. május 17 Fizika angol nyelven középszint Javítási-értékelési útmutató FIRST PART 1. C 2. B 3. A 4. B 5. B 6. A 7. B 8. B 9. C 10. A 11. C 12. A 13. B 14. C 15. A 16. C 17. A 18. A 19. A 20. C Award 2 points for each correct answer. Total: 40 points. írásbeli vizsga 1121 3/8 2012. május 17 Fizika angol nyelven középszint Javítási-értékelési útmutató SECOND PART Problem 1 Data: g = 10 m/s2, L = 30 cm, t1 = 0.15 s, s2 = 20 cm a) Writing down the formula for determining the position at which the first person catches the ruler and calculating it: 3 + 1 points s1 = g 2 ⋅ t1 = 11.3 cm, ie the first

person catches the ruler at about the 11 cm mark 2 b) Writing down the formula for determining the reaction time of the second person and calculating it: 2 + 1 points t2 = 2 ⋅ s2 = 0.2 s g g 2 ⋅ t 2 but make no further progress – 2 transformation or calculation – only one point is to be awarded here.) (Should the examinee write down the formula s2 = Writing down the formula for determining the speed of the ruler and calculating it: 2 + 1 points v2 = g ⋅ t 2 = 2 m s c) Determining whether the third person is able to catch the ruler: 3 points (may be divided) Because the distance covered by the ruler during the reaction time given is g s3 = (2t1 ) 2 = 45 cm (1 point), which is greater than the length of the ruler (1 point), the 2 third person will not be able to catch the ruler (1 point). It is not necessary to calculate the distance covered by the ruler explicitly. A textual argument is fully acceptable as long as it is clear that the examinee compares the distance

covered by the ruler to its length. (eg During twice the time of t1 the ruler covers four times the distance, which is greater than the overall length of the ruler.) Simply stating that the third person will not catch the ruler without any calculation or justification is worth one point only. Total: 13 points írásbeli vizsga 1121 4/8 2012. május 17 Fizika angol nyelven középszint Javítási-értékelési útmutató Problem 2 Data: mglass = 300 g, Tglass = 20 °C, mmilk = 200 g, Tmilk = 10 °C, Tfinal = 38 °C, cmilk = 4000 J J , cglass = 840 , Pnet = 90 W, Pnominal = 120 W. kg ⋅ °C kg ⋅ °C a) Determining the temperature change of the milk and the nursing bottle: 1 + 1 points Δ Tmilk = T final − Tmilk = 28 °C , Δ Tglass = T final − Tglass = 18 °C (It is not necessary to formulate the temperature changes explicitly. If the examinee uses the correct values later when calculating the heat transfer, full points are to be awarded.) Formulating the heat

transfer of the food warmer and calculating it: 4 + 2 points (may be divided) Q = mmilk ⋅ cmilk ⋅ ΔTmilk + m glass ⋅ c glass ⋅ ΔTglass (writing down the two terms 1 + 1 points), from which Q = 27 kJ (substitution in the two terms 1 + 1 point, calculation 2 points). b) Formulating the time required for the heating and calculating it: 3 + 2 points (may be divided) As the heat transferred is Q = Pnet ⋅ t (2 points), Q t= = 300 s = 5 minutes (rearranging the formula + calculation: 1 + 2 points). Pnet c) Formulating the amount of heat lost and calculating it: 2 + 2 points (may be divided) Since the nominal power of the heater is Pnominal = Pnet + Ploss (1 point), the heat loss is Qloss = Ploss ⋅ t = 9 kJ (formulation and calculation: 1 + 2 points) or: Since the nominal power of the heater is 120 W, the overall energy consumption is Qtotal = Pno min al ⋅ t = 36 kJ (formulation and calculation: 1 + 1 points), from which Qloss = Qtotal − Q = 9 kJ (formulation and

calculation: 1 + 1 points). Total: 17 points írásbeli vizsga 1121 5/8 2012. május 17 Fizika angol nyelven középszint Javítási-értékelési útmutató Problem 3/A Data: h = 6.67 · 10-34 Js, 1 eV = 16 · 10-19 J, c = 3 · 108 m/s a) Preparing a suitable graph and plotting the data: 6 points (may be divided) (In the plot, the properly scaled and labeled axes are worth 1 point each. The correct plotting of the data in the table is worth 2 points. If only 3 or 4 data points are plotted correctly, 1 point may be awarded. Drawing the line of best fit is worth 2 points) Ee (eV) 3 2 1 5 írásbeli vizsga 1121 6 7 6/8 Ephoton(eV) 2012. május 17 Fizika angol nyelven középszint Javítási-értékelési útmutató b) Determining the work function of silver: 4 points (may be divided) The work function of silver may be determined from any one of the data pairs in the table: Wout = E photon − Eelectron = 4.75 eV (formulation + calculation: 2 + 2 points),

(Should the examinee simply write down the basic formula of the photoelectric effect without relating it to the present case, only one point may be awarded.) or it may be determined from the intersection of the line of best fit and the horizontal axis (extending the line to the horizontal axis 2 points, reading the location of the intersection 2 points). c) Recognizing that the smallest photon energy for which electron ejection still occurs is equal to the work function: 2 points (Should the examinee fail to state this recognition, but use it later on in the calculation, the two points are to be awarded.) Formulating and calculating the greatest photon wavelength at which the ejection of electrons still happens: 6 points (may be divided) E photon = Wout = h⋅c λ (1 point), from which λ = h⋅c = 2.7 ⋅10 −7 m = 270 nm (rearranging, Wout conversion and calculation: 1 + 2 + 2 points). d) Determining the data missing from the table: 2 points (may be divided) The missing photon

energy may be determined via calculation: E photon = Ee + Wout = 6.27 eV (formulation + calculation: 1 + 1 points), or using the line of best fit on the graph, by reading the value. Total 20 points írásbeli vizsga 1121 7/8 2012. május 17 Fizika angol nyelven középszint Javítási-értékelési útmutató Problem 3/B (Each score may be divided) a) Explanation of the absence of electrocution: 5 points The voltage drop across the two legs of the bird is very small, so the current flowing through it is negligible. (Any similar phrasing is also acceptable.) b) Explanation of the electrocution: 2 points E.g The voltage difference between the legs and the wings of the bird is great or the birds legs and wings connect two points with a great voltage difference between them. (Any similar phrasing is also acceptable.) c) Explanation of the electrocution: 2 points E.g The voltage difference between the legs and the wings of the bird is great in this case as well, or the birds

legs and wings connect two points with a great voltage difference between them. (Any similar phrasing is also acceptable. The two points must be awarded also if the examinee answers question b) correctly and indicates here that the explanation is the same as that for question b). The examinee need not be aware of the fact that the wires carry different phases of a three-phase system.) d) Explaining the difference between different power lines: 3 points The distance between the wires of the higher voltage power lines is greater than that between the wires of a lower voltage power line. Therefore the chance that the wings of birds touch two wires at once is smaller. e) Phrasing two suggestions for measures to prevent electrocution: 4 + 4 points Any sensible suggestion may be accepted, even if it is not practical, for example because it is too expensive. Examples: insulation of the wires, insulation of the poles, usage of underground cables, usage of poles where the wires are farther

away from each other, fixing perching rods on the tops of the poles, etc. Total: 20 points írásbeli vizsga 1121 8/8 2012. május 17