Mechanical Aptitude Basic Electrical Circuits Flashcards
7 cards from real MECHANICAL APTITUDE practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Mechanical Aptitude Basic Electrical Circuits flashcards as text
A transformer has 200 turns on the primary coil and 50 turns on the secondary coil. If the primary voltage is 240V, what is the secondary voltage?
Answer: 60 volts
V_secondary = V_primary × (N_secondary / N_primary) = 240 × (50/200) = 240 × 0.25 = 60 volts.
Which instrument would you use to check whether a circuit is open or closed without energizing it?
Answer: Ohmmeter or continuity tester
An ohmmeter or continuity tester applies its own small voltage to measure resistance, detecting open (infinite resistance) or closed (low resistance) circuits safely.
What is the difference between AC (alternating current) and DC (direct current)?
Answer: DC flows only in one direction; AC reverses direction periodically
DC flows continuously in one direction, while AC periodically reverses direction, typically at 60 Hz in the US.
A wire carries 3 amps for 10 seconds. How many coulombs of charge have passed through it?
Answer: 30 coulombs
Charge = Current × Time = 3A × 10s = 30 coulombs.
What is electrical 'short circuit'?
Answer: An unintended low-resistance path that allows excess current to bypass the load
A short circuit creates a direct low-resistance path, causing extremely high current that can damage wiring and start fires.
In an electrical schematic, what does a zigzag line symbol typically represent?
Answer: A resistor
The zigzag line is the standard schematic symbol for a resistor in North American circuit diagrams.
If you double the cross-sectional area of a wire while keeping its length and material the same, what happens to its resistance?
Answer: Resistance is halved
Resistance is inversely proportional to cross-sectional area (R = ρL/A), so doubling area halves the resistance.