ASVAB Electronics Information Practice Test 862097 Results

	Your Results	Global Average
Questions	5	5
Correct	0	3.63
Score	0%	73%

Review

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

47% Answer Correctly

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

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.

The formula specifying Ohm's law is which of the following?

76% Answer Correctly

	\(V = {I \over R}\)
	V = IR
	\(V = {R \over I}\)
	V = I²R

Solution

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

3 A circuit with a 120-volt power supply is protected by a 25-amp circuit breaker. What is the largest number of watts loads on this circuit can safely use?

82% Answer Correctly

	1500 W
	2994 W
	3000 W
	3009 W

Solution

Wattage is current multiplied by voltage: W = IV. So, the maximum amount of power a 120-volt circuit with a 25A circuit breaker would allow is 120V x 25A = 3000 W.

Which of the following will help to prevent a short circuit?

74% Answer Correctly

	transistor
	diode
	resistor
	fuse

Solution

Fuses are thin wires that melt when the current in a circuit exceeds a preset amount. They help prevent short circuits from damaging circuit components when an unusually large current is applied to the circuit, either through component failure or spikes in applied voltage.

What type of current flows in only one direction in a circuit?

82% Answer Correctly

	alternating
	parallel
	direct
	series

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.