ASVAB Automotive Information Practice Test 663515 Results

Your Results Global Average
Questions 5 5
Correct 0 2.99
Score 0% 60%

Review

1

What is the primary difference between internal and external combustion engines?

48% Answer Correctly

where the power is developed

the type of fuel used

how the fuel is ignited

the air-fuel mix for optimum combustion


Solution

The primary difference between internal and external combustion engines lies in where the power is developed. In an internal combustion engine fuel is ignited and burned inside the same container where the power is developed while in an external combustion engine the fuel is ignited outside the engine and the resulting power sent to it.


2

What is the name of the proper ratio of air to fuel necessary so that an engine burns all fuel with no excess air?

62% Answer Correctly

ignition ratio

combustion ratio

stoichiometric ratio

residual ratio


Solution

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.


3

Modern car engines are cooled by:

81% Answer Correctly

liquid

air conditioner

ice

air


Solution

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.


4

What's the name of the high-voltage winding in the ignition coil?

51% Answer Correctly

primary coil winding

initial coil winding

battery coil winding

secondary coil winding


Solution

The ignition coil is a high-voltage transformer made up of two coils of wire. The primary coil winding is the low-voltage winding and has relatively few turns of heavy wire. The secondary coil winding is the high-voltage winding that surrounds the primary and is made up of thousands of turns of fine wire. Current flows from the battery through the primary coil winding which creates a changing magnetic field inside the secondary coil. This induces a very high-voltage current in the secondary coil which it feeds to the distributor.


5

What's the name of the low-voltage winding in the ignition coil?

57% Answer Correctly

tertiary coil winding

primary coil winding

secondary coil winding

distributor coil winding


Solution

The ignition coil is a high-voltage transformer made up of two coils of wire. The primary coil winding is the low-voltage winding and has relatively few turns of heavy wire. The secondary coil winding is the high-voltage winding that surrounds the primary and is made up of thousands of turns of fine wire. Current flows from the battery through the primary coil winding which creates a changing magnetic field inside the secondary coil. This induces a very high-voltage current in the secondary coil which it feeds to the distributor.