Free ASVAB Practice Tests | ASVAB Test Bank

Math Knowledge

Which types of triangles will always have at least two sides of equal length?

equilateral and isosceles

An isosceles triangle has two sides of equal length. An equilateral triangle has three sides of equal length. In a right triangle, two sides meet at a right angle.

Electronics Information

This circuit component symbol represents a(n):

diode

A diode allows current to pass easily in one direction and blocks current in the other direction. Diodes are commonly used for rectification which is the conversion of alternating current (AC) into direct current (DC). Because a diode only allows current flow in one direction, it will pass either the upper or lower half of AC waves (half-wave rectification) creating pulsating DC. Multiple diodes can be connected together to utilize both halves of the AC signal in full-wave rectification.

Mechanical Comprehension

What is the efficiency of a machine has work input of 100 ft⋅lb and work output of 35 ft⋅lb?

35%

Due to friction, a machine will never be able to utilize 100% of its work input. A certain percentage of that input will be lost in overcoming friction within the machine. Effeciency is a measure of how much of a machine's work input can be turned into useful work output and is calculated by dividing work output by work input and multiplying the result by 100:
\( Efficiency = \frac{Work_{out}}{Work_{in}} \times 100 \) \( = \frac{35 ft⋅lb}{100 ft⋅lb} \times 100 \) \( = 35% \) %

Automotive Information

Which of the following regulates the flow of coolant through the radiator?

thermostat

The thermostat controls coolant (and, through it, engine) temperature by regulating the flow of coolant through the radiator. A bypass tube allows coolant to bypass the radiator and flow back into the water pump when its temperature is low enough that the thermostat is closed.

Word Knowledge

The singer's prominence ensured that the concert would sell out.

renown

Importance.

Electronics Information

In electrical wiring, which of the following are proportional?

the diameter of the wire and the amount of the current

Current flow through a wire increases the temperature of the wire. If too small a wire is used, the wire will heat up causing a loss in conductivity and possibly a fire. The thicker in diameter a wire is, the more current it can carry without overheating.

Shop Information

The primary difference between a claw and a ball-peen hammer is which of the following?

their non-striking end

The most common striking tool is the hammer and the most common variety of hammer is the claw hammer. The claw hammer has two ends, one to drive nails and one to remove nails. Ball-peen hammers replace the claw with a rounded end that's used to round off the edges of metal pins and make gaskets.

Mechanical Comprehension

The standard unit of energy is the:

Joule

The Joule (J) is the standard unit of energy and has the unit \({kg \times m^2} \over s^2\).

Electronics Information

General current flow in a transistor is from __________ to __________.

collector, emitter

The transistor is the foundation of modern electronic devices. It is made entirely from semiconductor material (making it a solid state device) and can serve many different functions in a circuit including acting as a switch, amplifier, or current regulator. A transistor works by allowing a small amount of current applied at the base to control general current flow from collector to emitter through the transistor.

Electronics Information

The conductivity of an element depends on how many electrons occupy which electron shell?

outer

All electricity is the movement of electrons which are subatomic particles that orbit the nucleus of an atom. Electrons occupy various energy levels called shells and how well an element enables the flow of electrons depends on how many electrons occupy its outer (valence) electron shell.