ASVAB Automotive Information Practice Test 109400 Results

Your Results Global Average
Questions 5 5
Correct 0 3.16
Score 0% 63%

Review

1

What is the function of the alternator?

59% Answer Correctly

replaces the electrical energy that the car draws from the battery

charges the battery when the car is not running

provides AC power for the car's electrical components

converts motion from the wheels into DC power


Solution

An automobile's electrical system runs on DC power and the bulk of that power is supplied by the battery. The alternator converts the motion of the rotor into AC power which is then fed through the rectifier to convert it to DC power that both the car and the battery can use.


2

Which of the following is the result of combustion being initiated by a source other than the spark plug?

51% Answer Correctly

pre-ignition

ignition

pre-combustion

detonation


Solution

Normal combustion in an engine is initiated by a spark plug and results in the complete burning of the air-fuel mixture. If combustion is initiated by a source other than the spark plug, by a hot spot in the cylinder or combustion chamber for example, pre-ignition results. Detonation results if the air-fuel mixture explodes instead of burning. Detonation can cause extremes in pressure in the combustion chamber leading to engine damage.


3

Engine oil viscosity is rated using the format XW-XX with the number preceding the W indicating viscosity at __________ ℉ and the XX indicating viscosity at __________ ℃.

65% Answer Correctly

100, 100

0, 100

0, 0

100, 0


Solution

The primary component of the lubrication system is engine oil. Engines require oil blends with different thickness (viscosity) and additives depending on their operating conditions. Viscosity is rated using the format XW-XX with the number preceding the W (winter) rating the oil’s viscosity at 0 ℉ (-17.8 ℃) and the XX indicating viscosity at 100 ℃.


4

An overcooled engine:

73% Answer Correctly

is more efficient

generates more power

uses less gasoline

is less efficient


Solution

An overcooled engine is less efficient. During the power stroke, combustion heat pushes down the piston. If too much of this heat is lost to the cooling system, the fuel might not combust completely and contaminate the engine's lubricating oil diminishing its lubricating ability. Incomplete combustion of fuel also negatively affects the engine's fuel efficiency and power output.


5

Which of the following transfers the torque from the transmission to the drive wheels at a constant speed while accomodating the up and down movement of the suspension?

68% Answer Correctly

control arms

constant velocity (CV) joint

transfer case

springs


Solution

Constant velocity (CV) joints are located at both ends of a half shaft and their purpose is to transfer the torque from the transmission to the drive wheels at a constant speed while accomodating the up and down movement of the suspension. The inner CV joint connects the shaft to the transmission and the outer CV joint connects the shaft to the wheel.