| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.22 |
| Score | 0% | 64% |
Which of the following is not part of an engine's cooling system?
coolant |
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thermostat |
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radiator |
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air conditioner |
The purpose of an automobile engine's cooling system is to circulate coolant around the engine so it can absorb and dissipate heat. The water pump pumps coolant through the various components in the system and the radiator cools down coolant after it has heated up after passing through the engine. The thermostat controls the flow of coolant based on engine temperature while the cooling fan draws air through the radiator when the car isn't moving fast enough for unforced air to cool things down on its own.
Modern car engines are cooled by:
liquid |
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air conditioner |
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air |
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ice |
Modern car engines are cooled by liquid which circulates through the engine block and cylinder heads absorbing excess heat. This liquid is made up of half water and half antifreeze (commonly, ethylene glycol) which both keeps the water from freezing at low temperatures and raises its boiling point making heat transfer more efficient.
Just before the piston reaches top dead center, the spark plug fires and ignites the compressed air-fuel mixture. This describes which engine stroke?
power |
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compression |
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exhaust |
|
intake |
During the power stroke, just before the piston reaches top dead center, the spark plug fires and ignites the compressed air-fuel mixture. The resulting expansion due to combustion pushes the piston back down the cylinder toward bottom dead center.
What is the pimary advantage of using power brakes on a vehicle?
provides higher hydraulic pressure in the braking system |
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utilizes battery power to assist in braking |
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requires less brake fluid to operate the braking system |
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allows the use of antilock brakes |
Power brakes multiply the force a driver applies to the brake pedal using a vacuum booster connected to the engine intake manifold. This provides for much higher hydraulic pressure in the braking system than could be generated by the driver alone. Antilock brakes (ABS) use speed sensors and adjust the brake pressure at each wheel to prevent skidding and allow the driver more steering control in slippery conditions.
Cylinder air and fuel intake valves, exhaust valves, and mounts for spark plugs and fuel injectors are contained in the:
cylinder head |
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head gasket |
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manifold |
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piston ring |
Cylinders act as a guide for the pistons that translate the heat energy of combustion into the mechanical energy necessary to move a vehicle. Piston rings seal the piston to the cylinder to contain combustion gases and also regulate the oil distribution between the piston and cylinder wall. A cylinder head closes in the top of the cylinder forming the combustion chamber which is sealed by a head gasket (head). The head provides space for air and fuel intake valves, exhaust valves, and mounts for spark plugs and fuel injectors.