ASVAB Electronics Information Practice Test 291134 Results

Your Results Global Average
Questions 5 5
Correct 0 3.60
Score 0% 72%

Review

1

Silver and gold are among the most highly conductive elements. Why is copper used much more often as a conductor in electrical circuits?

80% Answer Correctly

copper is durable and relatively cheap

silver and gold are costly

silver and gold are brittle

all of these


Solution

All conductors have resistance and the amount of resistance varies with the element.  But, resistance isn't the only consideration when choosing a conductor as the most highly conductive elements like silver and gold are also more expensive and more brittle than slightly less conductive elements like copper. A balance needs to be struck between the electrical qualities of a material and its cost and durability.


2

This circuit component symbol represents a(n):

60% Answer Correctly

capacitor

transformer

inductor

resistor


Solution

An inductor is coiled wire that stores electric energy in the form of magnetic energy and resists changes in the electric current flowing through it. If current is increasing, the inductor produces a voltage that slows the increase and, if current is decreasing, the magnetic energy in the coil opposes the decrease to keep the current flowing longer. In contrast to capacitors, inductors allow DC to pass easily but resist the flow of AC.


3

A capacitor is often used for which of the following purposes?

68% Answer Correctly

to maintain power in a circuit when the primary power source is disconnected

to allow a small amount of current to control a large amount of current

as a primary power source

to convert alternating current into direct current


Solution

Capacitors store electricity and are used in circuits as temporary batteries. Capacitors are charged by DC current (AC current passes through a capacitor) and that stored charge can later be dissipated into the circuit as needed. Capacitors are often used to maintain power within a system when it is disconnected from its primary power source or to smooth out or filter voltage within a circuit.


4

This circuit component symbol represents a(n):

72% Answer Correctly

inductor

capacitor

diode

transistor


Solution

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.


5

Which of these materials is not a good conductor of electricity?

79% Answer Correctly

tin

gold

copper

air


Solution

All conductors have resistance and the amount of resistance varies with the element. In general, metals make the best conductors of electricity and non-metals make the worst conductors of electricity.