GRADE 12 JUNE 2017 PHYSICAL SCIENCES P1

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1 NATIONAL SENIOR CERTIFICATE GRADE 1 JUNE 017 PHYSICAL SCIENCES P1 MARKS: 150 TIME: 3 hours *JPHSCE1* This question paper consists o 1 pages, including a page data sheet.

2 PHYSICAL SCIENCES P1 (EC/JUNE 017) INSTRUCTIONS AND INFORMATION 1. Write your NAME and SURNAME in the appropriate space on the ANSWER BOOK.. Answer ALL the questions. 3. Non-programmable calculators may be used. 4. Appropriate mathematical instruments may be used. 5. Number the questions correctly according to the numbering system used in this question paper. 6. You are advised to use the attached DATA SHEETS. 7. The ormulae and substitutions must be shown in ALL calculations. 8. Give brie motivations, discussions, etc. where required. 9. Round o your inal numerical answers to a minimum o TWO decimal places. 10. Start EACH question on a NEW page. 11. All diagrams are not necessarily drawn according to scale.

3 (EC/JUNE 017) PHYSICAL SCIENCES P1 3 QUESTION 1: MULTIPLE-CHOICE QUESTIONS Four possible options are provided as answers to the ollowing questions. Each question has only ONE correct answer. Choose the best answer and write down A, B, C or D next to the question number (1.1 to 1.10) on your ANSWER BOOK. 1.1 When an object alls reely near the earth s surace, its acceleration is always A. increasing in a downward direction. B. decreasing in a downward direction. C. 9,8 m s - in an upward direction. D. 9,8 m s - in a downward direction. () 1. When two cars collide head-on, the collision is inelastic i A. the change in momentum is zero. B. the sum o their initial kinetic energies is not equal to sum o their inal kinetic energies. C. the sum o their initial kinetic energies is equal to sum o their inal kinetic energies. D. total linear momenta beore collision is not equal total linear momenta ater collision. () 1.3 A school bus suddenly comes to a stop, and all the backpacks on the loor start to slide orward. The backpacks slide orward because 1.4 A. the backpacks resist a change in their state o motion. B. there is a pushing orce applied by the loor on the backpacks. C. the backpacks experience a pulling orce in a orward direction. D. the weight o the backpacks decreased as the bus was stopping. () The diagram above shows a statue resting on a table. FG is the orce o gravity on the statue, FN is the orce o the table on the statue and F'N is the orce o the statue on the table. The action-reaction pair demonstrated in the above diagram is: A. (FG + F'N) and FN B. F'N and FN C. FG and F'N D. FG and FN ()

4 4 PHYSICAL SCIENCES P1 (EC/JUNE 017) 1.5 The diagram below shows a spacecrat orbiting above the earth. Motion r E r E The orce gravity on the spacecrat on earth is FE. What is the orce o gravity on the spacecrat when it orbits two earths radii rom the earth s center? A. 1 4 FE B. 4 FE C. 1 FE D. FE () 1.6 When a police car with a siren approaches you, it emits sound waves. The sound waves that reach you have a wavelength and a requency. A. shorter higher B. longer higher C. shorter lower D. longer lower () 1.7 A test charge placed in an electric ield around a negative point experiences an electrostatic orce o attraction (F). Which o the ollowing graphs best represents the relationship between the orce (F) and the distance (d) between the test charge and the point charge? A. B. C. D. ()

5 (EC/JUNE 017) PHYSICAL SCIENCES P An observer on the earth that observes an approaching light source. He will notice that the light rom the object will have a shorter wavelength because the distance between the waveronts (λ) A. increases as the source moves towards the observer. B. decreases as the source moves towards the observer. C. decreases as the source catches up with its emitted waves. D. increases as the source moves away rom its emitted waves. () 1.9 A orce or which the net work done in moving an object between two points is dependant o the path taken is called A. a non-conservative orce. B. an electrostatic orce between the surace and the object. C. a conservative orce. D. a pulling orce. () 1.10 Two identical balls, M and N, are both thrown rom a cli. Ball M is thrown directly upwards and N is thrown directly downwards. Both balls will hit the bottom o the cli. I both balls were given the same initial speed, which ball will hit the bottom o the cli with a greater velocity? A. Both balls with have the same velocity at the bottom o the cli B. Ball M C. Ball N D. Ball M will reach the bottom irst () [0] QUESTION.1 A person throws a ball upward into the air with an initial velocity o 15 m s -1. Ignore the eects o air resistance..1.1 What is the physics name given to any object, like the ball above, where ONLY the gravitational orce o the earth is acting on it? (1).1. Calculate how high it goes up beore coming down. (4).1.3 Calculate how long the ball is in the air beore it comes back to the hand. (3).1.4 Calculate the time it takes the ball to pass a point o 8 m above the person s hand. (5).1.5 Draw position vs. time graph indicating the ollowing times: at point o projection, at 8 m above the hand, at maximum height, back at the thrower s hand. (4). A stone is dropped rom the roo o a building. A second stone was thrown, rom the same height, straight down s ater the irst stone had been dropped with an initial velocity o 30 m s -1. Ater having covered the same displacement, the two stones reach the ground at the same time. How long did it take the second stone to reach the ground? (6) [3]

6 6 PHYSICAL SCIENCES P1 (EC/JUNE 017) QUESTION A gol ball o mass 0,045 kg is hit o the tee at a speed o 45 m s -1. The gol club was in contact with the ball or 3, s Deine the term impulse. () 3.1. Calculate the impulse imparted to the gol ball. (3) Calculate the average orce exerted on the ball by the gol club. () 3. A tennis ball o mass 60 g strikes the wall perpendicularly at a velocity o 1 m s -1. It rebounds at a velocity o 10 m s Calculate the change in momentum o the tennis ball. (5) 3.. What is the magnitude o impulse o the wall on the ball? (1) 3.3 A block o mass m =,0 kg slides down slides down a 30 incline which is 3,6 m high. At the bottom, it strikes a stationary block o mass M = 7,00 kg resting on a horizontal surace. 3,6 m 30 M Assume that all suraces are rictionless Deine the Principle o Conservation o Linear Momentum in words. () 3.3. The block o mass m stops immediately ater collision. Calculate the magnitude o the velocity o the block o mass M just ater collision. (6) [1]

7 (EC/JUNE 017) PHYSICAL SCIENCES P1 7 QUESTION A skier in the diagram below, initially at rest, has just begun descending a 30 slope. 30 Assuming that the coeicient o kinetic riction (µk) is 0, Draw a ree-body diagram o all the orces acting on the skier. (3) 4.1. Calculate her acceleration down the slope (5) Calculate the magnitude o the velocity she will reach ater 4,0 s. (3) 4. A system o two objects, an elevator and a counterweight, suspended by a pulley and light cable is shown in the diagram below. a E Elevator car me = kg a C Counterweight mc = kg The mass o the elevator with our people inside is me = kg and its mass is 850 kg when empty. The mass o the counterweight is mc = kg. Ignore the mass o the pulley and the mass o the cable Deine Newton s Second Law o motion in words. () 4.. Calculate the acceleration o the elevator. (6) 4..3 Calculate the tension in the cable. (3) []

8 8 PHYSICAL SCIENCES P1 (EC/JUNE 017) QUESTION A car is travelling along a straight horizontal road. A orce o 600 N is applied to the car in the direction that it is travelling, speeding it up. While it is speeding up it covers a distance o 30 m. Calculate the work done on the car. (3) 5. A box o mass 100 kg was resting on a lat horizontal surace when a orce o 300 N was applied to pull at acting at angle o 60 to the horizontal. The box moved a displacement o 6 m to the east while experiencing a rictional orce o 50 N Calculate the amount o work done by the rictional orce on the box. (3) 5.. Calculate the net work done on the box. (4) 5.3 The driver o a 800 kg car travelling at a speed o 0,5 m s -1 applies the car s brakes when a red light is observed. The car s brakes provide a rictional orce o N Deine the work-energy theorem in words. () 5.3. Determine the stopping distance o the car. (5)

9 (EC/JUNE 017) PHYSICAL SCIENCES P The diagram below shows a box that was stationary, being pushed with a constant orce o 450 N across a rictionless horizontal surace which is 60 cm long. The box then moves up an incline due to the same orce o 450 N. The coeicient o kinetic riction between the box and the inclined surace is 0, Calculate the net work done on the object as it moves rom point A and reaches point B with a velocity o 5 m s -1. (3) 5.4. What is magnitude o the kinetic riction experienced by the box as moves rom point B to point C? (4) Draw a ree body diagram o all orces acting on the box when it is at point C. (4) Calculate the net work done on the box as it reaches point C. (4) What would be the gravitational potential energy o the box at C? (3) [35]

10 10 PHYSICAL SCIENCES P1 (EC/JUNE 017) QUESTION The siren o a moving ambulance emits waves at a requency o 350 Hz. The requency o the sound as heard by the listener standing along the road is 400 Hz Deine the Doppler Eect. () 6.1. Was the ambulance moving towards or away rom the listener? Explain your answer, making special reerence to requency, waveronts and wavelength. (4) I the speed o sound in the air is 340 m s -1, determine the velocity at which the ambulance was moving. (4) 6. A police car travelling down a road at constant speed emits sound waves rom its siren. A lady stands on the side o the road with a detector which registers sound waves at a requency o 450 Hz as the police car approaches her. Ater passing her, and moving away at the same constant speed, sound waves o requency 390 Hz are registered. Assume that the speed o sound in air is 343 m s -1. Calculate: 6..1 The speed at which the ambulance is moving. (7) 6.. The requency at which the siren emits the sound waves. (3) [0] QUESTION Three point charges are in a straight line. Their charges are Q1 = C, Q = C and Q3 = C. The distance between Q1 and Q is 10 m and the distance between Q and Q3 is 4 10 m Deine Coulomb s Law in words () 7.1. What is the net electrostatic orce on Q due to the other two charges? (7) [9] TOTAL: 150

11 (EC/JUNE 017) PHYSICAL SCIENCES P1 11 DATA FOR PHYSICAL SCIENCES GRADE 1 PAPER 1 (PHYSICS) GEGEWENS VIR FISIESE WETENSKAPPE GRAAD 1 VRAESTEL 1 (FISIKA) TABLE 1: PHYSICAL CONSTANTS/TABEL 1: FISIESE KONSTANTES NAME/NAAM SYMBOL/SIMBOOL VALUE/WAARDE Acceleration due to gravity Swaartekragversnelling Universal gravitational constant Universele gravitasiekonstant Speed o light in a vacuum Spoed van lig in 'n vakuum Planck's constant Planck se konstante Coulomb's constant Coulomb se konstante Charge on electron Lading op elektron Electron mass Elektronmassa Mass o Earth Massa van Aarde Radius o Earth Radius van Aarde g 9,8 m s - G 6, N m kg- c 3, m s -1 h 6, J s k 9, N m C- -e -1, C me M RE TABLE : FORMULAE/TABEL : FORMULES MOTION/BEWEGING v v 1 Δx viδt a t 9, kg 5, kg 6, m 1 vi a t or/o Δy viδt a t v i v v i v vi a x or/o v vi a y Δx Δt or/o Δy Δt FORCE / KRAG F net ma p mv max s F net = μ N s Δt =Δp Δp = mv m m - mv i k = μ N k w mg 1 1 F =G or/o F=G g =G g =G d m m r M d or/o M r

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13 1 PHYSICAL SCIENCES P1 (EC/JUNE 017) WORK, ENERGY AND POWER/ARBEID, ENERGIE EN DRYWING F net ma p mv max s F net = μ N s Δt =Δp Δp = mv m m - mv i k = μ N k w mg 1 1 F =G or/o F=G g =G g =G d m m r M d WAVES, SOUND AND LIGHT/GOLWE, KLANK EN LIG v v v L L L s L b v v s v vb E = Wo + E k(max) or/o = Wo + Kmax 1 T v v E h or /o E where/waar 1 E h and/en W0 h0 and/en E k(max) = mvmax or/o ELECTROSTATICS / ELEKTROSTATIKA or/o K E h c 1 = max mv max M r kq Q 1 F E r kq r W V q F E q Q n = e or/o n = Q q e

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