ASVAB Electronics Information Practice Test 81371 Results

	Your Results	Global Average
Questions	5	5
Correct	0	3.25
Score	0%	65%

Review

1 Use Ohm's Law to calculate the value of resistance in this circuit if voltage is 400 volts and current is 5 amps.

80% Answer Correctly

	120 Ω
	240 Ω
	83 Ω
	80 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 = \( \frac{V}{I} \) = \( \frac{400}{5} \) = 80 Ω

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

79% Answer Correctly

	tin
	gold
	air
	copper

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.

In electrical wiring, which of the following are proportional?

50% Answer Correctly

	the length of the wire and the amount of the voltage
	the length of the wire and the amount of the current
	the diameter of the wire and the amount of the current
	the diameter of the wire and the amount of the voltage

Solution

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.

In metals, increasing the temperature typically _____________ conductivity.

50% Answer Correctly

	does nothing to
	eliminates
	decreases
	increases

Solution

All conductors have resistance and the amount of resistance varies with the element. Metals exhibit increased resistance (and, therefore, lower conductivity) as their temperature increases.

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

69% Answer Correctly

	reactance
	capacitance
	rectification
	inductance

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.