ASVAB Electronics Information Practice Test 6858 Results

	Your Results	Global Average
Questions	5	5
Correct	0	3.48
Score	0%	70%

Review

This circuit component symbol represents a(n):

55% Answer Correctly

	transformer
	fuse
	inductor
	potentiometer

Solution

Resistors are used to limit voltage and/or current in a circuit and can have a fixed or variable resistance. Variable resistors (often called potentiometers or rheostats) are used when dynamic control over the voltage/current in a circuit is needed, for example, in a light dimmer or volume control.

Which of the following statements about a capacitor is false?

77% Answer Correctly

	a capacitor remains charged even after the input voltage is removed
	it is safe to touch a capacitor with your hands as long as it is small
	to discharge a capacitor safely, use a high-wattage resistor comparable to the capacitance of the capacitor
	you should always discharge any capacitors before working on an electronic circuit

Solution

The purpose of a capacitor is to retain electric charge and it will do so even after its input voltage is removed. After the input voltage is removed, the capacitor will slowly discharge but, depending on the size and characteristics of the capacitor, discharging could take from a few minutes to a few years. So, it's never safe to touch a capacitor with your hands and you should make sure to discharge any capacitors in a circuit before working on it using an appropriately high-wattage resistor or a capacitor discharge tool.

3 Use Ohm's Law to calculate the value of voltage in this circuit if resistance is 20 Ω and current is 5.5 amps.

85% Answer Correctly

	121 V
	112 V
	107 V
	110 V

Solution

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

V = \( I \times R \) = \( 5.5 \times 20 \) = 110 V

Capacitors store:

69% Answer Correctly

	current
	resistance
	electricity
	capacitance

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.

Direct current flows from the __________ terminal of the voltage source to the __________ terminal.

62% Answer Correctly

	negative, positive
	positive, negative
	positive, positive
	negative, negative

Solution

Direct current flows in only one direction in a circuit, from the negative terminal of the voltage source to the positive. A common source of direct current (DC) is a battery.