Electronics Flashcards
7 cards from real ASVAB practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Electronics flashcards as text
What is the purpose of a bypass capacitor placed across a power supply pin on an integrated circuit?
Answer: To filter out high-frequency noise on the supply line
Bypass capacitors provide a low-impedance path to ground for high-frequency noise, keeping the supply voltage clean and stable.
In a transistor amplifier circuit, what region of operation is the transistor in when it acts as a switch in the 'ON' state?
Answer: Saturation
In saturation, both junctions are forward-biased and the transistor conducts maximally, acting like a closed switch.
What is the unit of inductance?
Answer: Henry
Inductance is measured in henries (H), named after Joseph Henry who discovered electromagnetic induction independently.
Two resistors of 6Ω and 3Ω are connected in parallel. What is the equivalent resistance?
Answer: 2Ω
For parallel resistors: 1/R = 1/6 + 1/3 = 1/6 + 2/6 = 3/6, so R = 2Ω.
Which type of logic gate produces a HIGH output only when ALL inputs are HIGH?
Answer: AND gate
An AND gate output is HIGH (1) only when every input is HIGH (1); any LOW input forces the output LOW.
What happens to the capacitive reactance (XC) of a capacitor as frequency increases?
Answer: It decreases
XC = 1/(2πfC), so as frequency (f) increases, XC decreases — capacitors pass high-frequency signals more easily.
What is the primary purpose of a heat sink attached to a transistor or voltage regulator?
Answer: To dissipate heat and prevent thermal damage
Heat sinks increase surface area to transfer heat away from the component into the surrounding air, preventing overheating.