Physical Sciences Grade 11 North West June 2019 QP

Physical Sciences Downloaded from hlayiso.com JUNE 2019 PROVINCIAL MID YEAR EXAMINATION MID YEAR EXAM GRADE 11 PHYSICAL SCIENCE MAY/JUNE 2019 QUESTION PAPER MARKS: 150 TIME: 3 hours This question paper consists of 13 pages, a graph paper, 3 data sheets and a periodic table. Demo NW/JUNE/PHYSC/ EMIS/6******* 1

Downloaded from hlayiso.com 8 Physical Sciences JUNE 2019 INSTRUCTIONS AND INFORMATION 1. Write your name on your ANSWER SHEET. 2. This question paper consists of TEN questions. Answer ALL the questions in the ANSWER SHEET. 3. Complete the table and QUESTION 9.5 on the GRAPH PAPER. 4. Start EACH question on a NEW page on the ANSWER SHEET. 5. Number the answers correctly according to the numbering system used in this question paper. 6. Leave ONE line between two sub questions, for example between QUESTION 2.1 and QUESTION 2.2. 7. You may use a non-programmable calculator. 8. You may use appropriate mathematical instruments. 9. You are advised to use the attached DATA SHEETS. 10. Show ALL formulae and substitutions in ALL calculations. 11. Round off your final numerical answers to a minimum of TWO decimal places. 12. Give brief motivations, discussions, et cetera where required. 13. Write neatly and legibly. Demo NW/JUNE/PHYSC/ EMIS/6******* 2

Physical Sciences Downloaded from hlayiso.com JUNE 2019 QUESTION 1: MULTIPLE-CHOICE QUESTIONS Four options are provided as possible answers to the following questions. Each question has only ONE correct answer. Write only the letter (A-D) next to the question number (1.1-1.10) on your ANSWER SHEET, for example 1.1 D. 1.1 Two forces are acting on a block as shown in the diagram. The resultant force in the horizontal direction is: A zero B 10 N to the right C 10 N to the left D 20 N to the right (2) 1.2 The graphs below show the relationship between the net force and the acceleration for two masses X and Y. Which one of the following statements is true? A The bodies have equal masses. B Body X has a smaller mass. C Body Y has a smaller mass. D The mass does not affect the gradient of the graphs. (2) 1.3 An artificial satellite circles around the earth at a height where the gravitational force is a ¼ of that at the surface of the earth. If the earth’s radius is R, the height of the satellite above the surface of the earth is A 2R B R C ½R D ¼R (2) Demo NW/JUNE/PHYSC/ EMIS/6******* 3

Downloaded from hlayiso.com 8 Physical Sciences JUNE 2019 1.4 A ray of light in a glass block strikes the edge of the block. The angle of incidence is much smaller than the critical angle. What happens to this ray? A It is completely reflected. B It is completely refracted. C It is partially reflected and partially refracted. D It is refracted at an angle of refraction of 90. (2) 1.5 A wave passes from a medium of high optical density to one of low optical density. Which ONE of the following is correct? A The frequency of the wave remains constant. B The speed of the wave remains constant. C The frequency of the wave increases. D The frequency of the wave decreases. (2) 1.6 The molecular shape of a molecule with the formula AB2 is either … A linear or bent. B linear or trigonal planar C linear or tetrahedral D linear or trigonal bipyramidal (2) 1.7 Iodine crystals (I2(s)) are soluble in ethanol (CH3CH2OH(l)) because the … A hydrogen bonds between ethanol molecules are much stronger than the dispersion forces between iodine molecules. B hydrogen bonds between ethanol molecules and the covalent bonds between iodine molecules are of comparable strength. C iodine molecules and the ethanol molecules are non-polar and “like dissolve like”. D London/dispersion forces between ethanol molecules and iodine molecules are of comparable strength and “like dissolve like”. (2) Demo NW/JUNE/PHYSC/ EMIS/6******* 4

Physical Sciences Downloaded from hlayiso.com JUNE 2019 1.8 Which ONE of the bonds between the atoms below has the highest polarity? A H–C B H – Cl C H–O D H–N (2) 1.9 0.5 dm3 of a gas at 20 °C and 130 kPa is cooled down while the volume is kept constant. The pressure on the gas at a temperature of -5 °C is … A 142,13 kPa. B 123,34 kPa. C 118,91 kPa. D 32,5 kPa. (2) 1.10 The calculation in QUESTION 1.9 is an illustration of … A Avogadro’s Law. B Charles’s Law. C Guy-Lussac’s Law. D The ideal gas law. (2) [20] Demo NW/JUNE/PHYSC/ EMIS/6******* 5

Downloaded from hlayiso.com 8 Physical Sciences JUNE 2019 QUESTION 2 The grade 11 learners learn that there is more than one way to determine the resultant of two vectors. One way is die COMPONENT METHOD. They want to use THIS METHOD to find the resultant of the forces acting on a bucket by the ropes from which the bucket is suspended. The bucket is stationary. 2.1 Define the term resultant. (2) 2.2 The tension in rope P is 130N at an angle of 30º to the vertical and the tension in Q is 91,92N at 45º to the vertical. Calculate the MAGNITUDE of the: 2.2.1 Horizontal components of P and Q respectively. (4) 2.2.2 Vertical components of P and Q respectively. (4) 2.2.3 Resultant of the horizontal components. (1) 2.2.4 Resultant of the vertical components. (1) 2.2.5 Resultant of the forces exerted by P and Q on the bucket. (1) 2.3 Determine the MASS of the bucket. (3) [16] Demo NW/JUNE/PHYSC/ EMIS/6******* 6

Physical Sciences Downloaded from hlayiso.com JUNE 2019 QUESTION 3 Keanon pulls a 10kg block, attached to a 5 kg block by a light, inextensible string of negligible mass, with a force of 50 N at an angle of 30º with the horizontal as shown below. The 10 kg block experience a kinetic frictional force of 20 N. The coefficient of kinetic friction between die surface and the 5 kg block is 0,2. 3.1 State Newton’s Second Law of Motion in words. (2) 3.2 Draw a labelled free body diagram showing all the forces acting on the 10 kg block. Note: No components of forces may be used in the diagram. (5) 3.3 Calculate the magnitude of the: 3.3.1 Normal force exerted on the 10kg block. (4) 3.3.2 Acceleration of the blocks. (7) 3.3.3 Tension in the string. (2) 3.4 How will the magnitude of the normal force calculated in QUESTION 3.3.1 be affected if the angle between the applied force and the horizontal decreases? Choose from INCREASES, DECREASES or REMAINS THE SAME. Explain your answer. (3) 3.5 Use Physics principles to explain why it is very dangerous when children are not secured in a child’s car seat when travelling by car. (3) [26] Demo NW/JUNE/PHYSC/ EMIS/6******* 7

Downloaded from hlayiso.com 8 Physical Sciences JUNE 2019 QUESTION 4 Three objects A, B and C are moving through space at right angles to each other. The mass of A is 3 kg and the mass of B is 8 kg. The distance between C and A is r and the distance between C and B is 2r. F CA is 35 N. 4.1 Define Newton’s Law of Universal Gravitation, in words. (2) 4.2 Calculate the force between C and B. (6) [8] QUESTION 5 5.1 Consider the following diagram of the light ray (c) striking an interface between air and water. The angle that the light ray makes with the surface of the water is 51°, as shown in the diagram. 5.1.1 Name the line AB. (1) 5.1.2 Calculate the angle of refraction for the light ray when it travels from air to water. (4) Demo NW/JUNE/PHYSC/ EMIS/6******* 8

Physical Sciences Downloaded from hlayiso.com JUNE 2019 5.1.3 On your ANSWER SHEET, redraw the sketch above and show the path of the light ray as it moves from air to water and emerges into the air again. LABEL YOUR SKETCH. (2) 5.1.4 What happens to the speed of light as the light moves from AIR to WATER? Write only INCREASES, DECREASES or REMAINS THE SAME. (2) 5.1.5 Explain your answer to QUESTION 5.1.4. (2) 5.2 Optical fibres are generally composed of silica, with an index of refraction of 1,44. The outer layer has a low index of refraction. 5.2.1 Why is the outer layer optically less dense than the inner layer? (2) 5.2.2 Name ONE use of optical fibres. (1) 5.2.3 Calculate how fast light travels in a silica fibre. (3) [17] QUESTION 6 Two learners investigate the patterns formed when light travels through two single slits, X and Y, of different widths. In the first experiment, they use monochromatic red light and observe the two patterns of different widths. 6.1 Name the wave phenomenon investigated by the learner. (1) 6.2 Which slit, X or Y, is the NARROWER slit? (1) 6.3 Explain the formation of the light and dark areas in the patterns as illustrated above. (2) 6.4 Learners now pass blue light through slit X. 6.4.1 Redraw the above pattern, observed when passing red light through slit X, unto your ANSWERSHEET. Below this pattern, draw the pattern that will be obtained for blue light. (2) 6.4.2 Explain the difference in these two patterns. (2) [8] Demo NW/JUNE/PHYSC/ EMIS/6******* 9

Downloaded from hlayiso.com 8 Physical Sciences JUNE 2019 QUESTION 7 Hydrogen reacts with oxygen to form water and carbon reacts with oxygen to form carbon dioxide. 7.1 Define the term covalent bond. (2) 7.2 Draw the Lewis structure for: 7.2.1 A water molecule (2) 7.2.2 A carbon dioxide molecule (2) 7.3 Write down the name of the intermolecular forces between: 7.3.1 Water molecules (1) 7.3.2 Carbon dioxide molecules. (1) 7.4 Write down the molecular shape of: 7.4.1 H2O (1) 7.4.2 CO2 (1) 7.5 Consider the average bond energies and bond lengths given below. 7.5.1 Define the term bond length. (2) 7.5.2 Compare the bond lengths and the bond energies of bonds 1, 2 and 3 given in the above table. Write the relationship between bond energy and bond length. (2) 7.5.3 Give a reason for the difference in bond lengths of bonds 3 and 4. (1) [15] Demo NW/JUNE/PHYSC/ EMIS/6******* 10

Physical Sciences Downloaded from hlayiso.com JUNE 2019 QUESTION 8 Consider the following substances with their formulae and approximate boiling points at atmospheric pressure. 8.1 Explain the difference in boiling points between by iodine and bromine referring to the relevant intermolecular forces and their influences. (3) 8.2 Can ethanol dissolve in water? Choose from YES or NO. (1) 8.3 Explain your answer to QUESTION 8.2 by referring to intermolecular forces. (3) 8.4 Hydrogen bromide has the highest vapour pressure of the substances in the table. 8.4.1 Define the term vapour pressure. (2) 8.4.2 Briefly explain why its vapour pressure is the highest. (2) [11] Demo NW/JUNE/PHYSC/ EMIS/6******* 11

Downloaded from hlayiso.com 8 Physical Sciences JUNE 2019 QUESTION 9 A learner investigates the relationship between the pressure and volume of a given amount of gas at a constant temperature. The following readings are obtained: Complete the table on the GRAPH SHEET and then answer the following questions. 9.1 Name and state the law that is being investigated in this experiment. (3) 9.2 Identify the following variables for this experiment: 9.2.1 Independent variable (1) 9.2.2 Dependent variable (1) 9.3 Name ONE variables that must be kept constant in this experiment. (1) 9.4 Write an investigative question for this experiment. (2) 1 9.5 Sketch a graph of volume (on y-axis) against pressure (on x-axis) using the GRAPH PAPER provided. (4) [12] Demo NW/JUNE/PHYSC/ EMIS/6******* 12

Physical Sciences Downloaded from hlayiso.com JUNE 2019 QUESTION 10 10.1 Name TWO properties of an ideal gas. (2) 10.2 Under which circumstances do real gases behave like an ideal gas? (2) 10.3 A diver dives down into the sea, to where the temperature is 10ºC and the pressure is 150kPa. He releases a bubble of air from his lungs. The volume of the bubble, when released is 5 cm3. Calculate the volume of the bubble when it reaches the surface of the sea, where the temperature is 25ºC. (4) 10.4 For what does STP stand? (1) 10.5 When 35 g of an unknown gas is pumped into a closed, empty 12 dm3 container at a constant temperatuur of 55ºC, the pressure inside the container is 285 kPa. 10.5.1 Calculate the number of mole gas in the container. (4) 10.5.2 Calculate the molar mass of the gas. (3) 10.5.3 Identify the gas. (1) [17] GRAND TOTAL: [150] Demo NW/JUNE/PHYSC/ EMIS/6******* 13

Downloaded from hlayiso.com 8 Physical Sciences JUNE 2019 NAME: TABLE AND GRAPH PAPER FOR QUESTION 9.5 Demo NW/JUNE/PHYSC/ EMIS/6******* 14

Physical Sciences Downloaded from hlayiso.com JUNE 2019 Demo NW/JUNE/PHYSC/ EMIS/6******* 15

Downloaded from hlayiso.com 8 Physical Sciences JUNE 2019 Demo NW/JUNE/PHYSC/ EMIS/6******* 16

Physical Sciences Downloaded from hlayiso.com JUNE 2019 TABLE 3: CHEMISTRY PHYSICAL CONSTANTS TABEL 3: CHEMIE FISIESE KONSTANTES NAME/NAAM SYMBOL/SIMBOOL VALUE/WAARDE Avogadro's constant NA 6,02 x 1023 mol-1 Avogadro-konstante Molar gas constant R 8,31 J∙K-1∙mol-1 Molêre gaskonstante Standard pressure p 1,013 x 105 Pa Standaarddruk Molar gas volume at STP Vm 22,4 dm3∙mol-1 Molêre gasvolume by STD Standard temperature T 273 K Standaardtemperatuur TABLE 4: CHEMISTRY - FORMULAE TABEL 4: CHEMIE - FORMULES p1V1 p 2 V2  pV  nRT T1 T2 m N n n M NA V n m n c OR/OF c Vm V MV Demo NW/JUNE/PHYSC/ EMIS/6******* 17

Downloaded from hlayiso.com 8 Physical Sciences JUNE 2019 Demo NW/JUNE/PHYSC/ EMIS/6******* 18