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 primary function of a computerized diagnostic scanner in a motor vehicle is to scan all systems on the vehicle and to adjust different sensors accordingly.
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 equipment used to test crankcase gases is the Combustion tester.
Step 3
4.3 What is the volumetric efficiency of a centrifugal blower?
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Answer
The volumetric efficiency of a centrifugal blower refers to its ability to fill the cylinder with air above the atmospheric pressure.
Step 4
4.4 Which ONE of the following is the cause of crankshaft vibrations?
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Answer
Crankshaft vibrations may occur if the crankshaft is not balanced.
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 of an engine 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 compression 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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Answer
To calculate the brake power, use the formula:
BrakePower=IndicatedPowerimesMechanicalEfficiency
Thus, the brake power is approximately 50 kW.
Step 8
4.8 What type of test is conducted with the equipment shown in FIGURE 4.8?
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Answer
The test conducted with the equipment shown is for testing the radiator cap.
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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Answer
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 tire wear shown 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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The outcome is referred to as a reverse gear.
Step 12
4.12 Which gear system is shown in FIGURE 4.12?
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Answer
Clarity on the gear system shown in FIGURE 4.12 is not provided, requiring further examination.
Step 13
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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The speed of the driven gear will be 2,500 r/min, calculated by multiplying the drive gear speed by the gear ratio.
Step 14
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.
