ASVAB Electronics Information Practice Test 651425 Results

Your Results Global Average
Questions 5 5
Correct 0 3.33
Score 0% 67%

Review

1

Which of the following is not an advantage of semiconductors over conductors?

49% Answer Correctly

a semiconductor exhibits increased conductivity with increased temperatures

a semiconductor's conductivity can be varied under an external electrical field

a semiconductor conducts current better than a conductor

materials to produce semiconductors are cheap and abundant


Solution

A semiconductor is a material that has a limited ability to conduct electrical current with conductivity between that of an insulator and that of a conductor. Silicon, a cheap and abundant material, is the most used semiconductor material although other materials are used in the electronics components made from semiconductors. The primary advantages of a semiconductor over a conductor is that the conductivity of a semiconductor can be varied under an external electrical field giving engineers precise control over complex circuits and, unlike conductors like metals, a semiconductor's conductivity increases with increased temperatures.


2

From what energy do photovoltaic cells produce electrical energy?

68% Answer Correctly

nuclear

sun

magnetic

chemical


Solution

A photovoltaic cell (also known as a solar cell) converts energy from the sun into electrical energy.


3 Use Ohm's Law to calculate the value of resistance in this circuit if voltage is 30 volts and current is 1 amps.
80% Answer Correctly
27 Ω
33 Ω
90 Ω
30 Ω

Solution

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

Solved for resistance, R = \( \frac{V}{I} \) = \( \frac{30}{1} \) = 30 Ω


4

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

69% Answer Correctly

reactance

capacitance

inductance

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.


5

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

68% Answer Correctly

to convert alternating current into direct current

as a primary power source

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


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.