Electricity and Circuits Flashcards
7 cards from real Bennett Mechanical Test practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Electricity and Circuits flashcards as text
What is the total current drawn from the source in a parallel circuit?
Answer: The sum of the branch currents
In a parallel circuit, the source current equals the sum of all branch currents.
What is the resistance of a circuit that draws 4 amps from a 12-volt battery?
Answer: 3 ohms
Resistance equals voltage divided by current, so 12 V ÷ 4 A = 3 ohms.
Which of these is an insulator?
Answer: Rubber
Rubber resists the flow of electricity and is used to insulate wires.
What component increases or decreases AC voltage in a circuit?
Answer: Transformer
A transformer steps voltage up or down using electromagnetic induction.
If a 60-watt bulb and a 100-watt bulb run at the same voltage, which draws more current?
Answer: The 100-watt bulb
At equal voltage, higher power means higher current, so the 100-watt bulb draws more.
What is a short circuit?
Answer: A low-resistance path that allows excessive current
A short circuit is an unintended low-resistance path that causes dangerously high current.
What is the function of a ground wire in an electrical system?
Answer: To provide a safe path for fault current to the earth
The ground wire safely directs fault current to earth, protecting people from shock.