SPINE ROAD HIGH SCHOOL TECHNOLOGY TEST 2 GRADE 9 SEPTEMBER 2017 EXAMINER: MRS N GOVENDER MODERATOR: MR LUKIE TIME: 1 HOUR 30 MINUTES INSTRUCTIONS

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1 SPINE ROAD HIGH SCHOOL TECHNOLOGY TEST 2 GRADE 9 SEPTEMBER 2017 EXAMINER: MRS N GOVENDER MODERATOR: MR LUKIE TIME: 1 HOUR 30 MINUTES INSTRUCTIONS 1. Answer all questions 2. Rule off after each question. 3. All drawings to be done in pencil. 4. Write neatly and legibly. 5. Please hand in your question paper. 100 GRADE A B C D E F G H I QUESTION ONE: CHOOSE THE CORRECT ANSWER. WRITE ONLY THE CORRECT NUMBER NEXT TO THE CORRESPONDING NUMBER. EG 2.1 C 2 x 5 [10]

2 1.1 Electrochemical cells are a) components that contains chemicals b) components that have positive poles only c) components that have negative poles only d) How we test Ohms Law 1.2 Light dependant resistors ( LDR s) a) senses light c) senses temperature b) senses moisture d) gives off light 1.3 The colour red black as 1 st band has a value of a) 2 b) 6 c) 0 d) An ammeter is used to test the a) voltage in a circuit b) resistance in a circuit c) current in a circuit d) none of the above 1.5 The following is an example a) Single pole single throw switch b) Single pole double throw switch c) Double pole double throw switch d) Diode QUESTION TWO: MATCH COLUMN A WITH COLUMN B. WRITE ONLY THE CORRECT LETTER NEXT TO THE CORRESPONDING NUMBER 2.1 A 2 X 5 = [10] COLUMN A COLUMN B 2.1 When two or more cells are A. Switch D connected together 2.2 An example of a control B. Diode A device 2.3 When current is allowed to C. Transistor B flow in one direction only 2.4 Has different colour bands D. Battery E 2.5 Amplifies current E. Resistor C QUESTION THREE: 2 X 7 = [14] Complete the missing information on the table below. Write down the number and answer next to it. Eg cell

3 Eg. NAME SYMBOL USE It supplies voltage to cell a circuit (3.1.1)closed switch LDR ( Light dependant resistor) (3.1.5)Thermistor (3.1.2) (3.1.3) Allows current to pass through when closed (3.1.4) It senses light Senses the change in temperature and changes the resistance LED Light emitting diode (3.1.6) (3.1.7) Used as lights and has different colours QUESTION FOUR: [17] 4.1 A B C Which of the following circuits are connected in series? [2] C Which of the following circuits are connected in parallel? [2] B Which of the circuits above have more strength? Give a reason for your answer. [2] 4.2 Use the circuit diagram below to complete the truth table [6]

4 Input A Input B Output Draw a circuit diagram with the following components cells in series, a 10kΩ, LED and a transistor. [5] QUESTION FIVE [22] 5.1 Explain how each of the following components are used in a circuit 3 x 2 [6] LED It is used as indicator lights and current only flows in one direction Capacitor Capacitors stores energy by storing electrical charge Diode It is a controlling device that is made up of an anode and cathode. Current flows in one direction only 5.2 Calculate the value of the voltage supply in a circuit if the resistor value is 4Ω and the current through the resistor is 2.5A [5] V = I x R = 2.5 A x 4Ω =10 V 5.3 Calculate the value of the resistance in the diagram below if the voltage is 12V and the current through the resistor is 2A. [4] R = V I = 12V 2A = 6 Ω

5 5.4 Look at figure below and answer the questions that follow Calculate the current through R₂. [3] I = V R = 6 V 12Ω = 0.5 A What will the current be through R₁? [2] 0.5 A. It is a series circuit What will the voltage drop across R₁ be? [2] 6 V. 12 V 6 V QUESTION SIX [16] Resistor colour bands indicates the value of a resistor. Use the table to calculate the following

6 6.1.1 What is the resistance of Resistor 1? [3] 470 Ω What is Resistor 1 s accuracy level? [2] 10% What is the resistance of Resistor 2? [3] 2200 Ω What is Resistor 1 s accuracy level? [2] 5% 6.3 Draw a resistor with the following resistance Ω kω 2 x 3 = [6]

7 QUESTION SEVEN [11] Look through the following information and answer the questions that follow A B 7.1 Write down the components that can be used in pictures A and B. Mention at least three (3) in each. 2 x 3 = [6] Push switch, SPST, sensor LED, Push switch, 7.2 Explain the AND principal in picture B. [2] The one will not work if the main switch is off. ( Any logial answer will be accepted) 7.3 What significance does the chains have in picture B? [2] It allows you to choose whether you want the fan on or the light. You can choose. ( Learner can have any logical answer) 7.4 Name the switch used in picture A. [1] Push switch