Mechanical Aptitude Basic Electrical Circuits Questions and Answers

Question 1

In a simple series circuit, if a 12-volt battery is connected across two resistors of 6 ohms and 3 ohms, what is the total current flowing through the circuit?

Accepted Answer

1.33 A

Answer

According to Ohm's Law (V=IR), current (I) is voltage (V) divided by total resistance (R). In a series circuit, the total resistance is the sum of individual resistances (R_total = R1 + R2). So, R_total = 6Ω + 3Ω = 9Ω. The current is then I = 12V / 9Ω = 1.33 A.

Question 2

Which of the following components is specifically designed to oppose the flow of electric current?

Accepted Answer

Resistor

Answer

A resistor is an electrical component that implements electrical resistance as a circuit element. Its primary function is to reduce current flow, adjust signal levels, divide voltages, etc. Capacitors store energy, inductors store energy in a magnetic field, and diodes allow current to flow in only one direction.

Question 3

Three light bulbs are connected in parallel to a power source. If one of the bulbs burns out, what happens to the other two bulbs?

Accepted Answer

They remain lit with the same brightness.

Answer

In a parallel circuit, each component is connected across the same two points, providing multiple paths for the current. If one bulb burns out (creating an open circuit in its branch), the other branches are unaffected and will continue to draw the same current from the source, so the remaining bulbs stay lit with unchanged brightness.

Question 4

A circuit has a voltage of 24V and a resistance of 6Ω. What is the power consumed by the circuit?

Accepted Answer

96 Watts

Answer

The formula for electrical power (P) can be expressed in several ways, including P = V²/R. Using the given values: P = (24V)² / 6Ω = 576 / 6 = 96 Watts.

Question 5

What is the primary function of a fuse in an electrical circuit?

Accepted Answer

To protect the circuit from excessive current

Answer

A fuse is a safety device consisting of a strip of wire that melts and breaks an electric circuit if the current exceeds a safe level. This protects the circuit's components from damage.

Mechanical Aptitude Test Practice Test

Mechanical Aptitude Test Practice Test

Mechanical Aptitude Basic Electrical Circuits Questions and Answers