NATIONAL SENIOR CERTIFICATE NASIONALE SENIOR SERTIFIKAAT GRADE 12/ GRAAD 12

Transcription

1 NM/ NME:. METROPOLE NORTH EUTION ISTRIT METROPOOL NOOR ONERWYS ISTRIK NTIONL SENIOR ERTIFITE NSIONLE SENIOR SERTIFIKT GRE 1/ GR 1 PHYSIL SIENES: PHYSIS (P1) FISIESE WETENSKPPE: FISIK (V1) SEPTEMER 016 MRKS/ Punte: 150 TIME/ Tyd: 3 hours/ 3 ure This question paper consists of 15 pages and 3 data sheets. Hierdie vraestel bestaan uit 15 bladsye en 3 gegewensblaaie.

2 Physical Sciences/P1 MNE September 016 INSTRUTIONS N INFORMTION Write your name in the appropriate space on the NSWER OOK. This question paper consists of ELEVEN questions. nswer LL the questions in the NSWER OOK. Start EH question on a NEW page in the NSWER OOK. Number the answers correctly according to the numbering system used in this question paper. Leave ONE line between two sub questions, for example between QUESTION.1 and QUESTION.. You may use a non-programmable calculator. You may use appropriate mathematical instruments. YOU RE VISE TO USE THE TTHE T SHEETS. Show LL formulae and substitutions in LL calculations. Round off your FINL numerical answers to a minimum of TWO decimal places. Give brief motivations, discussions, et cetera where required. Write neatly and legibly.

3 Physical Sciences/P1 3 MNE September 016 QUESTION 1: MULTIPLE-HOIE QUESTIONS Four options are provided as possible answers to the following questions. Each question has only ONE correct answer. hoose the correct answer and write only the letter ( ) next to the question number ( ) in the NSWER OOK e.g E 1.1 If the total momentum of a system is changing: particles of the system must be exerting forces on each other the system must be under the influence of gravity the system must move at constant velocity a net external force must be acting on the system () 1. n object is fired vertically upward. While it is moving upward: its velocity and acceleration are both upward its velocity is upward and its acceleration is downward its velocity and acceleration are both downward its velocity is downward and its acceleration is upward () 1.3 Newton s first law of motion can be represented mathematically by: F net = ma F net Δt = mδv F = - F If F = 0, then v is constant () 1.4 Two spherical objects attract each other with a gravitational force F. If the distance between the centres of the spheres is doubled, the force of attraction between them is: ¼ F ½ F F F ()

4 Physical Sciences/P1 4 MNE September The work done on an object moving in a straight line on a ROUGH horizontal surface is equal to the change in the object s momentum. gravitational potential energy. kinetic energy. acceleration. () 1.6 Sound waves are produced by the hooter of a truck that is approaching a stationary observer.at a constant velocity. ompared to the sound waves detected by the driver of the truck, the sound waves detected by the observer have a greater wavelength. frequency. period. speed. () 1.7 Which graph represents the relationship between the magnitude of the electrostatic force, F E, between two charged spheres and the distance, r, between the centres of the spheres? FE r FE FE r FE r r ()

5 Physical Sciences/P1 5 MNE September In the circuit shown below the resistances of the battery, ammeter, switch and connecting wires are negligible. The voltmeter has a very high resistance. V 1 S How are the readings on the ammeter and voltmeter affected if switch S is opened? MMETER VOLTMETER ecrease Increase ecrease No change Increase No change Increase ecrease () 1.9 The diagram below shows possible transitions of electrons between energy levels of a particular element. Which transition would produce the line of SHORTEST WVELENGTH on the emission spectrum of the element? Transition a Transition c Transition d Transition e ()

6 Physical Sciences/P1 6 MNE September The maximum kinetic energy of an electron ejected from the surface of a metal by a photon depends on: The photon s frequency only The metal s work function only oth the photon s frequency and the metal s work function The photon s intensity and the metal s work function () [0] QUESTION (Start on a new page.) block of mass kg is connected with a light inextensible string that is hanging over a frictionless pulley, to another block of mass X kg. force of 0 N is applied to the right at an angle of 0 o to the horizontal on the kg block while the block accelerates at 4 m s - to the left. kg 0 o 0 N X kg The coefficient of kinetic friction between the kg block and the surface is 0,. Ignore the effects of air friction..1 State Newton s second law of motion in words (). raw a labelled free-body diagram indicating LL the forces acting on the kg block. (5).3 alculate X, the mass of the hanging block. (8) [15]

7 Physical Sciences/P1 7 MNE September 016 QUESTION 3 (Start on a new page.) ball of mass 100 g is thrown vertically upwards from the ground with a velocity of 3,9 m s -1. The graph below illustrates how its velocity varies with time during the first few seconds of its motion. Ignore the effects of air resistance. velocity (m s -1 ) 3,9,5 E time (s) -3,9 When the ball hits the ground for the first time, it is in contact with the ground for 0,1 s. 3.1 efine the term projectile () 3. alculate the: 3..1 Maximum height the ball reaches above the ground (3) 3.. Time taken by the ball to reach the ground (3) 3.3 alculate the magnitude of the force the ball exerts on the ground while it is in contact with the ground (3) 3.4 raw a position-time graph for the motion of the ball ( to E) with the ground as zero position. learly indicate the following on your graph: the times,,, and E. (3) [14]

8 Physical Sciences/P1 8 MNE September 016 QUESTION 4 (Start on a new page.) man in a boat is stuck in the middle of a lake. In an attempt to reach the shore, 60 m away, the man throws an object of mass 1 kg horizontally at a speed of 10 m s -1 in the direction shown in the diagram below. 1 kg 10 m s -1 The combined mass of the man and the boat is 100 kg. The effects of air resistance and friction between the water and the boat can be ignored. 4.1 Write down the principle of conservation of linear momentum in words, () 4. How will the force exerted on the object compare with the force exerted on the man-boat combination? hoose from GRETER THN, SMLLER THN or EQUL TO. (1) 4.3 Give a reason for the answer to QUESTION 4. (3) 4.4 alculate the time it will take to reach the shore after throwing the object. (6) [1]

9 Physical Sciences/P1 9 MNE September 016 QUESTION 5 (Start on a new page.) n object of mass 4 kg starting from rest slides down an inclined plane of length 3 m as shown in the diagram below. The plane is inclined by an angle of 30 o to the ground. The coefficient of kinetic friction μ k is 0,.. 4 kg 3 m 30 o t the bottom of the plane, the mass slides along a rough horizontal surface with a coefficient of kinetic friction 0,5 until it comes to rest. 5.1 raw a labelled free body diagram indicating LL the forces acting on the object as it slides down the incline (3) 5. Write down the work-energy theorem in words () alculate the: 5.3 istance the object slides along the rough horizontal surface. (8) [13]

10 Physical Sciences/P1 10 MNE September 016 QUESTION 6 (Start on a new page.) traffic officer is standing on the side of a road where the speed limit is 100 km h -1. He hears the hooter of a car that is travelling at constant velocity on this road. The hooter emits sound waves of frequency 433,64 Hz. The wavelength of the sound waves detected by the traffic officer is 0,7 m. The speed of sound in air is 340 m.s alculate the frequency of the detected sound wave. (3) 6. State the oppler-effect in words. () 6.3 Is the car travelling towards or away from the traffic officer? Give a reason for the answer () 6.4 Is the car exceeding the speed limit? Support your answer by means of a calculation. (6) 6.5 How will the frequency of the sound waves detected by the traffic officer be affected if the car travels at a lower constant velocity? hoose from GRETER THN, LESS THN or THE SME S. (1) [14]

11 Physical Sciences/P1 11 MNE September 016 QUESTION 7 (Start on a new page.) Three charged particles Q 1, Q and Q 3 carrying charges of + x 10-5, - x 10-4 and + x 10-4 respectively are positioned as shown in the diagram below. Q 3 = x10-4 N 0,4 m W S E 0,5 m Q 1 = x10-5 Q = x State oulomb s Law in words () 7. alculate the number of excess electrons on charge Q. (3) 7.3 alculate the net electrostatic force exerted on charge Q 1 by the charges Q and Q 3. (6) [11] QUESTION 8 (Start on a new page.) Two charged particles Q 1 and Q are placed 30 cm apart as shown in the diagram below. Point P is 10 cm east of charge Q. N 3 µ -5 µ P Q 1 Q W E 30 cm S 8.1 efine the electric field at point in words () 8. alculate the magnitude and direction of the net electric field at point P (6) [8]

12 Physical Sciences/P1 1 MNE September 016 QUESTION 9 (Start on a new page.) 9.1 The circuit below is setup to determine the emf (ε) and internal resistance (r) of a fresh battery. emf? S r V The data obtained from the investigation is plotted and the following graph is obtained. V(V) Graph of potential difference versus current 6,0 4,0,0 0 0, 0,4 0,6 0,8 1,0 1, I() Write down the value of the emf of the battery (1) 9.1. alculate V internal if the current in the circuit is 0,4 (3)

13 Physical Sciences/P1 13 MNE September battery with an internal resistance of 0,5 Ω and an emf (ε) of 4 V is connected in a circuit, as shown below. With switch S closed, the highresistance voltmeter (V) has a reading of,6 V ε = 4 V 0,5 Ω S V,6 V Ω R 16 Ω 5 Ω efine the term emf of 4 V in terms of work done. () 9.. alculate the power dissipated in the 16 Ω resistor (7) 9..3 alculate the current passing through resistor R (4) Resistor R is removed from the circuit 9..4 Will the power dissipated in the 16 Ω resistor INRESE, ERESE or REMIN ONSTNT? Explain the answer without doing any calculations. (4) [1]

14 Physical Sciences/P1 14 MNE September 016 QUESTION 10 (Start on a new page.) simplified diagram of an generator is shown below. The direction of the current in the coil is from to. N S 10.1 In which direction is the coil being rotated? hoose from LOKWISE or NTILOKWISE (1) The output potential difference (V max ) of the generator shown in the above diagram is 311,13 V at 50 Hz. 10. Starting from the position shown in the diagram above, sketch a graph of output voltage versus time for one complete cycle of the coil. () 10.3 n electrical device connected to the generator shown above, consumes 9,45 x 10 6 J of energy in two hours. alculate the: Power rating of the electrical device. (3) Maximum current through the electrical device when connected to the generator shown above (5) [11]

15 Physical Sciences/P1 15 MNE September 016 QUESTION 11 (Start on a new page.) uring an investigation, light of different frequencies is shone onto the metal cathode of a photocell. The maximum kinetic energy of the emitted photoelectrons is measured. The graph below shows the results obtained. Graph of maximum kinetic energy versus frequency Maximum kinetic energy (J) E x x x Frequency (Hz) 11.1 efine the term work function in words. () 11. alculate the work function of the metal. (3) 11.3 alculate the magnitude of maximum kinetic frequency E 1 indicated on the graph. (4) The intensity of the incident light of frequency 15 x Hz is now increased How will the maximum velocity of the ejected photoelectron be affected? hoose from INRESE, ERESE or REMIN THE SME. Give a reason for the answer. () [11] TOTL 150

16 Physical Sciences/P1 16 MNE September 016 T FOR PHYSIL SIENES GRE 1 PPER 1 (PHYSIS) GEGEWENS VIR FISIESE WETENSKPPE GR 1 VRESTEL 1 (FISIK) TLE 1: PHYSIL ONSTNTS/TEL 1: FISIESE KONSTNTES NME/NM SYMOL/SIMOOL VLUE/WRE cceleration due to gravity Swaartekragversnelling g 9,8 m s - Universal gravitational constant Universele gravitasiekonstant G 6,67 x N m kg Speed of light in a vacuum Spoed van lig in 'n vakuum c 3,0 x 10 8 m s -1 Planck's constant Planck se konstante h 6,63 x J s oulomb's constant oulomb se konstante k 9,0 x N m harge on electron Lading op elektron -e -1,6 x Electron mass Elektronmassa m e 9,11 x kg Mass of Earth Massa van arde M 5,98 x 10 4 kg Radius of Earth Radius van arde R E 6,38 x 10 6 m TLE : FORMULE/TEL : FORMULES MOTION/EWEGING vf v f 1 = vi + a t Δx Δy = v iδt + a t v i + v f v i + v f = v i + a x or/of v f = v i + a y Δx = Δt or/of Δy = Δt FORE / KRG F net = ma p = mv max fs = μsn FnetΔt =Δp Δp = mv - f mv i m1m m1m F =G or/of =G d r f k 1 = v iδt + a t or/of = μ N k w = mg M d or/of M =G r F g =G WORK, ENERGY N POWER/REI, ENERGIE EN RYWING g

17 Physical Sciences/P1 17 MNE September 016 W = F x cos θ U = mgh or/of E P = mgh 1 K = mv or/of W nc E = k 1 mv = K + U or/of Wnc = Ek + Ep W net = K or/of Wnet = Ek K = K f K i or/of Ek = Ekf Eki W P = t P ave = Fv ave / P gemid = Fv gemid WVES, SOUN N LIGHT/GOLWE, KLNK EN LIG v = f λ 1 T = f f v ± v f L L L = s fl fb v ± v s v ± vb + E o E k(max) or/of o max = W v ± v = E = hf or /of E = W + K where/waar 1 E = hf and/en W 0 = hf0 and/en E k(max) = mv max or/of ELETROSTTIS / ELEKTROSTTIK K E = h c λ 1 = max mv max kq Q 1 F= r kq E = r W V = q F E = q Q n = e or/of n = Q q e

18 Physical Sciences/P1 18 MNE September 016 URRENT ELETRIITY / STROOMELEKTRISITEIT V R = I emf ( ε )= I(R + r) emk ( ε )= I(R + r) Rs = R1 + R = R R R p 1 q = I t W = Vq W = VI t W = I R t W = V Δt R W P = Δt P = VI P = I R V P = R LTERNTING URRENT / WISSELSTROOM/ Imax I rms = / I I = wgk maks V V = max rms / V V = wgk maks P P = I / Pgemiddeld = V wgk I wgk ave V rms rms = R / P = R ave I rms gemiddeld I wgk Vrms P = ave R / V Pgemiddeld = R wgk