4.1 What is the function of the computerised diagnostic scanner used on a motor vehicle?
A - NSC Mechanical Technology Automotive - Question 4 - 2020 - Paper 1
Question 4
4.1 What is the function of the computerised diagnostic scanner used on a motor vehicle?
A. To scan whether the engine leaks gases from the cylinder during the indu... show full transcript
Worked Solution & Example Answer:4.1 What is the function of the computerised diagnostic scanner used on a motor vehicle?
A - NSC Mechanical Technology Automotive - Question 4 - 2020 - Paper 1
Step 1
4.1 What is the function of the computerised diagnostic scanner used on a motor vehicle?
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Answer
The function of a computerised diagnostic scanner in a motor vehicle is primarily to scan all systems on the vehicle and to adjust different sensors effectively to ensure optimal performance.
Step 2
4.2 Which ONE of the following pieces of equipment is used to test the crankcase gases?
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Answer
The piece of equipment used to test the crankcase gases is the Gas analysing tester.
Step 3
4.3 What is the volumetric efficiency of a centrifugal blower?
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The volumetric efficiency of a centrifugal blower refers to the ability to fill the cylinder with air above the atmospheric pressure.
Step 4
4.4 What is the following of the cause of crankshaft vibrations?
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Crankshaft vibrations can be caused by the taper of the crankshaft journal, especially if the engine is not balanced properly.
Step 5
4.5 Which ONE of the following is an important method used to increase the compression ratio of an engine?
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An important method to increase the compression ratio is to fit a thinner gasket between the cylinder block and the cylinder head.
Step 6
4.6 What does the symbol X in FIGURE 4.6 indicate?
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The symbol X in Figure 4.6 indicates the piston length.
Step 7
4.7 What will be the brake power of the engine if the engine delivers a mechanical efficiency of 83,34% with 60 kW indicated power?
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To calculate the brake power, you can use the formula:
ext{Brake Power} = rac{ ext{Indicated Power} imes ext{Mechanical Efficiency}}{100}
Substituting the given values:
ext{Brake Power} = rac{60 imes 83.34}{100} = 50 ext{ kW}
Step 8
4.8 What type of test is conducted with the equipment shown in FIGURE 4.8?
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The type of test conducted with the equipment shown in Figure 4.8 is Testing for water leaks.
Step 9
4.9 Which ONE of the following is an advantage of an electrical fuel pump in a motor vehicle?
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An advantage of an electrical fuel pump in a motor vehicle is its low operation noise.
Step 10
4.10 What type of tyre wear is shown in FIGURE 4.10?
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The type of tyre wear shown in Figure 4.10 is Kingpin-edged wear.
Step 11
4.11 What type of drive is the outcome when the planet carrier is locked for a double epicyclic gear?
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When the planet carrier is locked for a double epicyclic gear, the outcome is typically a third or top gear.
Step 12
4.13 What will be the speed of a driven gear if the gear ratio of a gear train is given as 5 : 1 and the drive gear rotates at 500 r/min?
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To find the speed of the driven gear, use the gear ratio:
ext{Speed of Driven Gear} = rac{ ext{Drive Gear Speed}}{ ext{Gear Ratio}} = rac{500}{5} = 100 ext{ r/min}
Step 13
4.14 Which ONE of the following is the function of the rotor assembly in an alternator charging system?
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The function of the rotor assembly in an alternator charging system is to provide a rotary electro-magnet.
