NTIONL CERTIFICTE (VOCTIONL) PHYSICL SCIENCE (First Paper) NQF LEVEL 3 NOVEMBER 2009 (10021003) 29 October (X-Paper) 09:00 12:00 Non-programmable calculators may be used. Candidates may use drawing instruments. This question paper consists of 10 pages, a 2-page answer sheet and a 1-page formula sheet.
(10021003) -2- NC1810(E)(O29)V TIME: 3 HOURS MRKS: 150 INSTRUCTIONS ND INFORMTION 1. 2. 3. 4. 5. 6. 7. 8. 9. Write your examination number (and centre number if applicable) in the appropriate spaces on the NSWER SHEET and NSWER BOOK provided. nswer LL the questions. nswer SECTION on the attached NSWER SHEET. nswer SECTION B in the NSWER BOOK provided. Number the answers according to the numbering system used in this question paper. data sheet is attached for your use. Give brief motivations and discussions, if required. LL final answers must be accurately approximated to TWO decimal places. Write neatly and legibly.
(10021003) -3- NC1810(E)(O29)V SECTION nswer this section on the attached NSWER SHEET. QUESTION 1: ONE-WORD ITEMS Give ONE word/term for ECH of the following descriptions. Write only the correct word/term next to the question number (1.1 1.5) on the attached NSWER SHEET. 1.1 1.2 1.3 1.4 1.5 The unit of mass defined as the mass of a platinum-iridium cylinder kept at the International Bureau of Weights and Measures at Sevres near Paris The rate of change of velocity The area under a velocity-time graph The state of an object when all the forces acting on it balance one another The property of a body that tends to resist the body's state of motion [5] QUESTION 2: MTCHING ITEMS Choose an item from COLUMN B that matches a description in COLUMN. Write only the letter ( H) next to the question number (2.1 2.5) on the attached NSWER SHEET. COLUMN COLUMN B 2.1 2.2 device that can store electrical charge n instrument which measures electrical potential difference B C transformer ammeter friction 2.3 2.4 The gradient of a displacement time graph The force resisting the motion of solid surfaces in contact D E F weight voltmeter velocity 2.5 device used to increase or decrease current and voltage G H acceleration capacitor (5 1) [5]
(10021003) -4- NC1810(E)(O29)V QUESTION 3: TRUE OR FLSE Indicate whether the following statements are TRUE or FLSE. Choose the answer and write only ' true' or 'false' next to the question number (3.1 3.5) on the attached NSWER SHEET. If the statement is FLSE, write the CORRECT statement. 3.1 3.2 3.3 3.4 3.5 The acceleration of an object depends directly upon the mass of the object. When the forces acting on an object are in equilibrium, they have a zero resultant. One Newton is the force that will give an object of mass 1 kg an acceleration of 1 m s -2. high-pitched note has a low frequency. Resonance is the tendency of a system to oscillate at higher amplitude at some frequencies than at other frequencies. [10] QUESTION 4: MULTIPLE-CHOICE QUESTIONS Various options are given as possible answers to the following questions. Choose the correct answer and make a cross (X) in the block next to the question number (4.1 4.5) on the attached NSWER SHEET. 4.1 Which ONE of the following pairs contains one vector and one scalar quantity? B C D Speed and distance Velocity and acceleration Electric field strength and force Electric field strength and power 4.2 Two forces 20 N and 60 N acting at a point. 20 N 60 N Ө s the angle Ө between the forces varies between 0 and 180, the magnitude of the resultant force F res B C D is always less than 20 N. is always more than 60 N. varies between 40 N and 80 N. varies between 20 N and 60 N.
(10021003) -5- NC1810(E)(O29)V 4.3 In the diagram, the bulb is connected as shown. If was to burn out, what will happen to the potential difference across the bulb? B C D Becomes zero Becomes infinite Remains as before Becomes equal to the cell EMF 4.4 The unit of electric potential is B C D joule per second. joule per coulomb. newton per coulomb. volt per metre. 4.5 n object which is charged positively has B C D gained electrons. a shortage of electrons. an excess of electrons. a shortage of neutrons. [15] TOTL SECTION : 35
(10021003) -6- NC1810(E)(O29)V SECTION B INSTRUCTIONS ND INFORMTION 1. 2. 3. nswer SECTION B in the NSWER BOOK provided. In all calculations, formulae and substitutions must be shown. Round off your answers to TWO decimal places. QUESTION 5: MESUREMENTS 5.1 Which instrument will you use to measure each of the following: 5.1.1 5.1.2 The time it takes to run 100 m The current in an electric circuit 5.2 Which units are used to measure the following: 5.2.1 5.2.2 The mass of a potato The distance between Pretoria and Johannesburg [4] QUESTION 6: MECHNICS 6.1 body of mass 60 kg is suspended by a light, inelastic rope, which is attached to a horizontal beam (FIGURE 1). second string is attached at point P on the first rope and pulled with a horizontal force of F until the first rope forms an angle of 55 with the vertical. The body is then held stationary in this position (FIGURE 2). P 55 P F 60 kg 60 kg 6.1.1 6.1.2 FIGURE 1 FIGURE 2 How many forces act at the point P in FIGURE 2? What is the magnitude of the resultant of the forces acting at point P in FIGURE 2?
(10021003) -7- NC1810(E)(O29)V 6.1.3 6.1.4 What is the magnitude of the force with which the earth attracts the body? Determine by calculation (a rough diagram must also be included) the magnitude of force F. (6) 6.2 car is driven at 25 m s -1 in a municipal area. When the driver sees a traffic officer at a speed trap, he realises he is travelling too fast. He immediately applies the brakes of the car while still 100 m away from the speed trap. 100 m 6.2.1 6.2.2 The municipal speed limit is 16,6 m s -1. Calculate the minimum deceleration which the car must have to avoid exceeding the speed limit when it reacts the speed trap. Calculate the time from the instant the driver applies brakes until he reaches the speed trap. ssume that the car's velocity, when reaching the trap, is 16,6 m s -1. [21] QUESTION 7 Your study group wants to determine the weight of a friend. You have a 3 m long plank, PQ, having a mass of 8 kg. You set up the plank with the pivot at X, 0,5 m away from point P. Your friend stands at point Y, 0,2 m away from the pivot. In order to balance the plank horizontally, a mass of 2 kg is hung 2 m away from the pivot. 0,5 m 2 m P P X 8 kg Qm Q 0,2 m 2 kg 7.1 7.2 Write down the TWO conditions or laws which must be satisfied in order to keep the beam at equilibrium position (horizontal). Draw a labelled force diagram indicating LL the forces acting on the plank while the plank remains horizontal. 7.3 Use the laws you used in QUESTION 7.1 and calculate the weight of your friend. Show LL calculations. (6) [13]
(10021003) -8- NC1810(E)(O29)V QUESTION 8: WVES, SOUND ND LIGHT 8.1 8.2 8.3 8.4 8.5 8.6 certain object vibrates with a period of 0,04 s and generates waves with a wavelength of 80 mm. Calculate the propagation speed of the waves. Complete the following table by comparing the eye and a camera. Position of object Nature and size of image Position of image The way in which light is controlled EYE CMER Draw a ray diagram to indicate how a convex lens can be used as a magnifying glass. The focal point of the lens must be indicated clearly. Name an optical instrument in which a convex lens is used as a magnifying glass. Explain why the pitch of the sound caused by the wings of a mosquito is higher than that of many other flying insects. Explain the difference between astigmatism and short-sightedness. (8) (5) [26] QUESTON 9: ELECTRICITY ND MGNETISM 9.1 transformer is an important application of electromagnetic induction. It is manufactured by winding copper wire around a soft iron core. Transformers operate on the principle of mutual induction. transformer in a science laboratory is used to change 220 V to 12 V needed for a ticker timer to operate. 9.1.1 9.1.2 9.1.3 Explain what is meant by electromagnetic induction. Explain why a soft iron core is used. Is this a step-up or step down transformer? 9.2 When you place a current-carrying wire in a magnetic field, the wire experiences a force. 9.2.1 9.2.2 What is the name given to this phenomenon? Explain THREE ways in which the force on the wire can be increased.
(10021003) -9- NC1810(E)(O29)V 9.3 Lightning occurs when there is a large difference in electric potential between a thundercloud and the ground and the base of the clouds. particular lightning flash transfers 4,5 C of charge in 5 x 10-4 s. 9.3.1 9.3.2 If a potential difference of 220 000 V exists between the ground and the clouds, calculate the amount of energy transferred by the charge as the lightning flashes. Calculate the current in this lightning flash. 9.4 small metal ball, carrying a charge of +4 x 10-9 C, is placed on an insulated stand. 9.4.1 9.4.2 9.4.3 Draw the electric field pattern around the charged ball. Define, in words, electric field strength. Calculate the magnitude of the electric field strength at a point 0,5 m from the charge. [29] QUESTION 10 Study the circuit diagram above and answer the following questions. The three cells in the sketch are connected in series. R 1, R 2 and R 3 represent three identical globes, each with a resistance of 2 Ω. 10.1 Switch S 1 and S 2 are closed. 10.1.1 10.1.2 Which globe(s) will burn? What reading do you expect on ammeter?
(10021003) -10- NC1810(E)(O29)V 10.2 Switches S 1, S 2 and S 3 are now all closed. 10.2.1 10.2.2 10.2.3 10.2.4 How does the brightness of globes R 1 and R 3 compare? Give a full explanation. Calculate the total resistance of the circuit. Calculate the reading on ammeter. Calculate the potential difference across the R 1 resistor. (5) 10.3 Switch S 1 is now opened and switch S 2 and S 3 remain closed. What reading do you expect on ammeter? [22] TOTL SECTION B: 115 GRND TOTL: 150
(10021003) -11- NC1810(E)(O29)V NTIONL CERTIFICTE (VOCTIONL) PHYSICL SCIENCE LEVEL 3 PPER 1 (PHYSICS) TBLE 1: PHYSICL CONSTNTS NME SYMBOL VLUE cceleration due to gravity g 9,8 m.s -2 Speed of light in vacuum c 3,0 x 10 8 m.s -1 Gravitational constant G 6,67 x 10-11 Nm 2. kg -2 Coulomb's constant k 9,0 x 10 9 N m 2 C -2 Charge of an electron e - -1,6 x 10-19 C Electron mass m e 9,11 x 10-31 kg TBLE 2: FORMULE MECHNICS V = u + at E p = mgh v 2 = u 2 + 2as M = load/effort S = ut + ½ at 2 VR = effort distance/load distance F = mg W = F x S E k = ½ mv 2 Efficiency = M/VR F = ma E p = mgh F = G m 1 m 2 / r 2 E k = ½ mv 2 WVES, SOUND ND LIGHT V = f λ T = 1/f F = v / λ MGNETISM ND ELECTRICITY R = r 1 + r 2 + r 3 Q = It 1/R = 1/r 1 +1/ r 2 + 1/r 3 E = IR + Ir V = IR V = W/Q F = kq 1 Q 2 /r 2 E = F/q E = kq/r 2 E = F/q W = Wes E = V/d C = Q/V P = VI
(10021003) -12- NC1810(E)(O29)V NSWER SHEET EXMINTION NUMBER: NTIONL CERTIFICTE (VOCTIONL) PHYSICL SCIENCE PPER 1 LEVEL 3 SECTION QUESTION 1 1.1 1.2 1.3 1.4 1.5 [5] QUESTION 2 2.1 2.2 2.3 2.4 2.5 [5] QUESTION 3 3.1 3.2 3.3 3.4 3.5 [10]
(10021003) -13- NC1810(E)(O29)V QUESTION 4 1.1 B C D 1.2 B C D 1.3 B C D 1.4 B C D 1.5 B C D (5 3) [15] TOTL SECTION : 35