| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.17 |
| Score | 0% | 63% |
When a car engine is running, what provides electrical current to recharge the battery and power the electrical system?
battery |
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solenoid |
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alternator |
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camshaft |
Once the engine is running, the alternator provides electrical current to recharge the battery and power the electrical system. The alternator is driven by the engine's crankshaft and produces alternating current (AC) which is then fed through a rectifier bridge to convert it to the direct current (DC) required by the electrical system. A voltage regulator controls the output of the alternator to maintain a consistent voltage (approx. 14.5 volts) in the electrical system regardless of load.
Coolant is circulated through the engine by the:
water jacket |
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water pump |
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radiator |
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camshaft |
The water pump is driven by a belt connected to the crankshaft and ensures that coolant moves through the engine and radiator.
The radiator is responsible for tranferring heat from the coolant to:
outside air |
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engine block |
|
thermostat |
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cylinder heads |
The radiator is responsible for tranferring heat from the coolant to the outside air. Radiator hoses transfer coolant to and from the engine to the radiator and a radiator cap maintains pressure in the cooling system to increase the boiling point of the coolant mixture and thus allow it to absorb more heat.
The spark plugs fire a few extra degrees before top dead center when the engine is running faster. In this case the engine's timing is:
synchronous |
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retarded |
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advanced |
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asynchronous |
Ignition timing defines the point in time at the end of the compression stroke that the spark plug fires. Measured in number of degrees before top dead center (BTDC), the exact point that the spark plugs initiate combustion varies depending on the speed of the engine. The timing is advanced (the spark plugs fire a few more degrees BTDC) when the engine is running faster and retarded when it's running slower.
Which of the following is not an advantage that disc brakes have over drum brakes?
provide a larger contact area |
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provide more braking force |
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use less brake fluid |
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are more easily cooled |
Brakes utlize friction to slow vehicle tires. Drum brakes employ a cast iron drum that roates with the vehicle axle. When hydraulic pressure is applied to the brake assemblies at the wheels, internal pistons expand and push brake shoes outward into contact with the brake drum slowing the rotation of the axle. More powerful disc brakes operate by pinching a rotating disc betweeen two brake pads and allow for a larger surface area to contact the disc, provide more force, and are more easily cooled.