Faculty of Engineering

Size: px

Start display at page:

Download "Faculty of Engineering"

Cameron Moore
5 years ago
Views:

1 T'IHITIIBIH UI'IIVERSI'I'Y Tz F OF SCIENCE HHD TECHNOLOGY E: W: Faculty of Engineering Office 0fthe Dean: InStem FACULTY OF ENGINEERING UNIT: lnstem QUALIFICATION: Introduction to Science, Technology, Engineering and Mathematics QUALIFICATION CODE: O4STEM LEVEL: 4 COURSE: Introduction to Physics A DATE: June 2017 COURSE CODE: IPH401S SESSION: DURATION: 3 Hours MARKS: 100 FIRST OPPORTUNITY EXAMINATION PAPER EXAMINER: Ms Ilana Malan Ms Oksana Kachepa MODERATOR: Mr Anthony Apata THIS PAPER CONSISTS OF 7 PAGES (EXCLUDING THIS FRONT PAGE) INSTRUCTIONS Answer all questions. Write all the answers in ink. No books, notes, correction fluid (Tippex) or cell phones allowed. Pocket calculators are allowed. You are not allowed to borrow or lend any equipment or stationary. Use graph paper for Question 16.1 and 16.2 All FINALANSWERS must be rounded off to THREE DECIMAL PLACES. AII CONSTANT VALUES on page 7.

2 SECTION A - TOTAL MARKS 30 This section consists of ten (10) questions. Each question carries 3 marks. Choose the correct answer and clearly indicate your answer. Question 1 [3] The distance between the two telephone poles is 50 m. When a 1 kg bird lands on the telephone wire midway between the poles, the wire sags 0,2 m. How much tension does the bird produce in the wire? 486,443 N 705,321 N 613,622 N 574,295 N Question 2 [3] A motorist drives north for 30 min at 85 km/h and then stops for 15 min. He then continues north, travelling 130 km in 2 h. What is his average velocity? 18,563 m/s 17,268 m/s 16,396 m/s 17,424 m/s Question 3 [3] Peter throws a ball upward at an angle 8 with an initial velocity of 21,0804 m/s. The ball reaches a maximum height of 20 m in 3,5 seconds. At what angle did he throw the ball? 70 to the vertical 70 to the horizontal 21,08 to the vertical 21,08 to the horizontal

3 Question 4 [3] The force exerted by the wind on the sails of a sailboat is 390N north. The water exerts a force of 180N east. If the boat has a mass of 270 kg, what are the magnitude and direction of its acceleration? 1,591 65,2250 1,729 63,4710 3, ,235 4, ,392O Question 5 [3] The builder is pushing a 50 kg wheelbarrow across level terrain with a horizontal force of 50 N and does 400] of work. If he exerts the same force at an angle of 45 degrees with respect to the horizontal and moves the wheelbarrow through the same distance, how much work does he do on the wheelbarrow? 153, , ,843] 85, 672J Question 6 [3] A ball of mass 0,6 kg is thrown at a wall. It strikes the wall with a speed of 1,6 m/s. If the collision is perfectly elastic, what will be the speed of the ball after collision? 0,5 m/s 1,6 m/s 2,0 m/s 0,4 m/s

4 WsinG Question 7 [2] Choose the correct answer for the equation of the forces acting on an object being kept stationary on an incline. Fr + WsinG = Fappned ('3) Fr = Fapplied (C) (cl) Fr = Fapplied Fr = Wsine Question 8 [3] What is the frequency of the oscillator below? Displacement/mm Time/ ms 80 Hz 800 Hz 400 Hz 125 Hz Question 9 [3] Oxygen has a molar mass of 16 g/mol. What volume will 200 g this gas occupy at 25 C and a pressure of3 atm. 0,306 m3 8,543 x 10'3 m3 0,102 m ,44 m3

5 Question 10 [4] A 1,5 kg iron horseshoe initially at 600 0C is dropped into a bucket containing 20 kg of water at 25 0C. 120 kj of heat is lost to the environment. What is the final temperature of the water-horseshoe system? (C) 29,604 0c 67,834 0c 98,357 0c 28,187 C

6 TOTAL 12 SECTION B - MARKS 70 This section consists of seven (7) questions. Answer ALL the questions. Question 11 [10] 11.1 Explain how you would use the conditions for equilibrium in determining an unknown force in a system of forces that are in equilibrium Determine analytically the magnitude and direction of the equilibrant the following forces: 0 ; 35 ; 140 ; 230 force of (3) (7) Question 12 [10] 12.1 When is a physical quantity called a vector? 12.2 Explain the motion of the object in Figure 1 from O s to 12 s Determine the speed and velocity of the object in Figure 1 from O s s. (2) (5) (3) Displacement-Time Graph (m) Displacement Time (s) Figure 1 5

7 Question 13 [15] 13.1 Describe the forces that create a torque of a couple. (3) 13.2 A 90 cm long metre rule with a mass of 250 g is pivoted at its centre, which is also the centre of mass. Three loads of weights 2 N, F and 4 N are positioned on the metre rule at the 14 cm, 31 cm and 88 cm marks respectively Construct the beam, clearly indicating the positions of all the forces and the pivot. (4) Determine the magnitude of the unknown load F that will keep the beam in equilibrium. (3) The pivot is moved to the 30 cm mark. At what position should an additional load of 183 N be placed to keep the beam in equilibrium? (5) Question 14 [11] 14.1 State the Principle of conservation of momentum. (2) 14.2 A 1200 kg car travelling initially with a speed of 25 m/s in an easterly direction crashes into the rear end of a 9 t truck moving in the same direction at 20 m/s. The velocity of the car right after the collision is 18 m/s to the east What is the velocity of the truck right after collision? (3) What percentage of mechanical energy is lost in collision? (4) State the forms of energy to which the mechanical energy was converted. (2) Question 15 [6] A rollercoaster car has a mass of 205 kg and is being pulled upwards on the track with a cable. The incline of the track is 32 and the cable attached to the car makes and angle of 9 with the track Determine the power required to pull the car at a constant velocity of 14,4 km/h. Express you answer in MW. (3) 15.2 Determine the tension in the calbe. (3)

8 Question 16 [9] A 125 g object is attached to the end of a horizontal spring. The object is displaced 5 cm to the right from its equilibrium position and then released, initiating simple harmonic motion with a frequency of4 Hz and amplitude of 5 cm Draw the displacement-time graph. (4) 16.2 Make a sketch of velocity-time graph using displacement time graph. The maximum value of velocity is not required. (5) Question 17 [9] 17.1 Differentiate between heat capacity and specific heat capacity of a substance. (3) 17.2 How much energy is required to change a 40 g ice cube from ice at -10 0C to steam at 110 0C? (6) The End Constants: g = 9,81 m/s2 ciron = 452 J/kgK owner: 4,2 kj/kgk cm: 2108 J/kgK Lf= 335 kj/kg LV=,26 MJ/kg Csteam = 2,02 kj/kgk 1 atm = Pa R = 8,31 J/molK

NATIONAL SENIOR CERTIFICATE GRADE 12 PHYSICAL SCIENCES: PHYSICS (P1) COMMON TEST JUNE 2014

NATIONAL SENIOR CERTIFICATE GRADE 12 PHYSICAL SCIENCES: PHYSICS (P1) COMMON TEST JUNE 2014 MARKS: 100 TIME: 2 hours This question paper consists of 9 pages and 2 data sheets. *PHSCE1* Physical Sciences