ASVAB Electronics Information Practice Test 645170 Results

	Your Results	Global Average
Questions	5	5
Correct	0	2.73
Score	0%	55%

Review

Which of the following is not a characteristic of direct current?

48% Answer Correctly

	cannot easily travel distances without power loss
	used to power your cell phone
	an example power source is a generator
	electrons flow in only one consistent direction

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 DC is a battery. In contrast to the constant one-way flow of direct current, alternating current changes direction many times each second. Electricity is delivered from power stations to customers as AC because it provides a more efficient way to transport electricity over long distances.

A capacitor to an electronic circuit is like a _______________ to a house?

67% Answer Correctly

	storage shed
	driveway
	safe
	gate

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.

Which of the following statements about a capacitor is false?

77% Answer Correctly

	you should always discharge any capacitors before working on an electronic circuit
	to discharge a capacitor safely, use a high-wattage resistor comparable to the capacitance of the capacitor
	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.

Which of the following is not true about a line drop?

43% Answer Correctly

	it is addressed by raising voltage and lowering current across the transmission line
	it is addressed by raising current and lowering voltage across the ransmission line
	it is a decrease in voltage between two points on a line
	it is caused by resistance

Solution

Electricity is delivered from power stations to customers as AC because it provides a more efficient way to transport electricity over long distances. A line drop is a decrease in voltage between two points on an electrical transmission line due to resistance in the line. A lower current and higher voltage across the line will help compensate for the line drop.

Which of the following is not a common type of battery?

41% Answer Correctly

	power-cycle
	deep-cycle
	dry cell
	wet cell

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. The three most common types of batteries are dry cell (used in small devices like TV remotes), wet cell (used for cars), and deep-cycle (storage batteries used primarily for backup and emergency power).