| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.34 |
| Score | 0% | 67% |
The two major types of vehicle braking systems are:
drum and disc |
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disc and shoe |
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drum and shoe |
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hydraulic and shoe |
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.
Just before the piston reaches top dead center, the spark plug fires and ignites the compressed air-fuel mixture. This describes which engine stroke?
compression |
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power |
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intake |
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exhaust |
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.
Which of the following statements about v-type cyllinder arrangement is false?
common in motorcycles, cars, and trucks |
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engine is shorter than an inline engine |
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has two rows of cylinders |
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has an odd number of cylinders |
A v-arrangement has two rows of cylinders in a V-shaped block with a crankshaft at the bottom of the V. Any even number of cylinders is possible in this configuration from the V-2 that's commonly used in motorcycles up to V-12 or bigger for large trucks. The V design produces a shorter engine than an in-line cylinder configuration and allows for better air-fuel distribution.
What is the name of the proper ratio of air to fuel necessary so that an engine burns all fuel with no excess air?
stoichiometric ratio |
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ignition ratio |
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combustion ratio |
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residual ratio |
The stoichiometric ratio defines the proper ratio of air to fuel necessary so that an engine burns all fuel with no excess air. For gasoline fuel, the stoichiometric ratio is about 14.7:1 or for every one gram of fuel, 14.7 grams of air are required. Too much air results in a lean air-fuel mixture that burns more slowly and hotter while too much fuel results in a rich mixture that burns quicker and cooler.
Which of the following is not a component in the engine lubrication system?
pickup tube |
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pressure relief valve |
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oil filter |
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differential |
In engine lubrication, oil remains in the oil pan until the engine is turned on. It then gets sucked up the pickup tube by the oil pump and pressurized. This pressure is moderated by the pressure relief valve and the oil is fed through the oil filter into the engine to lubricate it.