ASVAB Electronics Information Practice Test 257867 Results

Your Results Global Average
Questions 5 5
Correct 0 3.27
Score 0% 65%

Review

1

Which of the following is not a characteristic of a step-up transformer?

54% Answer Correctly

the primary voltage is higher than the secondary voltage

the secondary voltage is higher than the primary voltage

has more turns in the secondary winding than in the primary winding

increases voltage


Solution

As their names indicate, a step-up transformer is used to step up or increase voltage and a step-down transformer is used to step down or decrease voltage. In a step-up transformer, the secondary voltage is higher than the primary voltage and it has more turns in the secondary winding than in the primary winding.


2

The conversion of alternating current (AC) into direct current (DC) is called:

69% Answer Correctly

inductance

capacitance

reactance

rectification


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.


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 convert alternating current into direct current

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

as a primary power source


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

The valence shell of a conductor is how full of electrons?

52% Answer Correctly

full

more than half full

half full

less than half full


Solution

Conductors are elements that allow electrons to flow freely. Their valence shell is less than half full of electrons that are able to move easily from one atom to another.


5 Use Ohm's Law to calculate the value of voltage in this circuit if resistance is 80 Ω and current is 6.5 amps.
85% Answer Correctly
520 V
780 V
523 V
173.33 V

Solution

Ohm's law specifies the relationship between voltage (V), current (I), and resistance (R) in an electrical circuit: V = IR.

V = \( I \times R \) = \( 6.5 \times 80 \) = 520 V