ASVAB Electronics Information Practice Test 382170 Results

	Your Results	Global Average
Questions	5	5
Correct	0	3.41
Score	0%	68%

Review

Which of the following can conduct electricity under some conditions but not others?

82% Answer Correctly

	resistor
	semiconductor
	conductor
	insulator

Solution

Semiconductors have valence shells that are exacly half full and can conduct electricity under some conditions but not others. This property makes them useful for the control of electrical current.

2 A circuit with a 120-volt power supply is protected by a 20-amp circuit breaker. What is the largest number of watts loads on this circuit can safely use?

82% Answer Correctly

	2400 W
	800 W
	7200 W
	2402 W

Solution

Wattage is current multiplied by voltage: W = IV. So, the maximum amount of power a 120-volt circuit with a 20A circuit breaker would allow is 120V x 20A = 2400 W.

Inductance is a factor in which of the following?

44% Answer Correctly

	determining energy stored by a capacitor
	an AC circuit
	batteries connected in serial
	a DC circuit

Solution

Inductance is a property of an AC circuit (or a component in an AC circuit) that quantifies resistance to changes in current. The current in an AC circuit is continuously changing and inductive reactance (the opposition to change) depends both on the inductance of the circuit or component and the rate at which the current is changing.

Which of the following statements about a capacitor is false?

77% Answer Correctly

	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
	it is safe to touch a capacitor with your hands as long as it is small
	a capacitor remains charged even after the input voltage is removed

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.

A solid state device has which of the following characteristics?

53% Answer Correctly

	made entirely from insulative material
	made entirely from conductive material
	made from a mix of conductive and insulative material
	made entirely from semiconductor material

Solution

The transistor is the foundation of modern electronic devices. It is made entirely from semiconductor material (making it a solid state device) and can serve many different functions in a circuit including acting as a switch, amplifier, or current regulator. A transistor works by allowing a small amount of current applied at the base to control general current flow from collector to emitter through the transistor.