Mechanical Aptitude Test Mechanical Aptitude Basic Electrical Circuits 1 — Questions and Answers
Question 1: In a series circuit with three resistors of 4 ohms, 6 ohms, and 10 ohms, what is the total resistance?
- 6.7 ohms
- 20 ohms (Correct answer)
- 10 ohms
- 4 ohms
Correct answer: 20 ohms
In a series circuit, total resistance is the sum of all individual resistances: 4 + 6 + 10 = 20 ohms.
Question 2: A circuit has a voltage of 12 volts and a current of 2 amperes. What is the resistance?
- 24 ohms
- 10 ohms
- 6 ohms (Correct answer)
- 14 ohms
Correct answer: 6 ohms
Using Ohm's Law, R = V / I = 12 / 2 = 6 ohms.
Question 3: Which of the following best describes a conductor?
- A material that blocks the flow of electrons
- A material that allows electrons to flow freely (Correct answer)
- A material that stores electrical charge
- A material that converts electricity to light
Correct answer: A material that allows electrons to flow freely
A conductor is a material with low resistance that allows electrons to move freely through it; metals like copper are common examples.
Question 4: What happens to current in a series circuit if one component burns out (open circuit)?
- Current doubles in the remaining components
- Current flows only through the burned-out component
- Current stops flowing through the entire circuit (Correct answer)
- Current remains the same in all other components
Correct answer: Current stops flowing through the entire circuit
In a series circuit, all components share the same single path. If that path is broken anywhere, current cannot flow at all.
Question 5: A light bulb is rated at 60 watts and operates on 120 volts. What current does it draw?
- 2 amperes
- 0.5 amperes (Correct answer)
- 7200 amperes
- 60 amperes
Correct answer: 0.5 amperes
Using P = V × I, rearranged to I = P / V = 60 / 120 = 0.5 amperes.
Question 6: Which component in a circuit is designed to protect against excessive current by breaking the circuit?
- Capacitor
- Resistor
- Fuse (Correct answer)
- Transformer
Correct answer: Fuse
A fuse contains a thin wire that melts and breaks the circuit when current exceeds a safe level, protecting other components from damage.
Mechanical Aptitude Test Mechanical Aptitude Basic Electrical Circuits 1
In a series circuit with three resistors of 4 ohms, 6 ohms, and 10 ohms, what is the total resistance?