Mechanical Aptitude Basic Electrical Circuits Questions and Answers 3

Question 1

What is the power dissipated by a 100Ω resistor with 2A flowing through it?

Accepted Answer

400W

Answer

Power can be calculated using P = I²R. With 2A through a 100Ω resistor: P = (2)² × 100 = 4 × 100 = 400W.

Question 2

What happens to the brightness of bulbs in a series circuit when one bulb is removed?

Accepted Answer

All remaining bulbs go out

Answer

In a series circuit, removing one component breaks the single current path, causing all remaining components to lose power. The circuit becomes open, and no current flows to any of the remaining bulbs.

Question 3

Which type of current periodically reverses its direction of flow?

Accepted Answer

Alternating current (AC)

Answer

Alternating current (AC) periodically reverses direction, typically in a sinusoidal pattern. In most countries, AC power alternates at 50 or 60 Hz. Direct current flows in only one direction.

Question 4

A wire's resistance increases when which of the following changes occurs?

Accepted Answer

The wire length increases

Answer

Resistance is directly proportional to the length of a conductor (R = ρL/A). Increasing the wire length increases the distance electrons must travel, resulting in more collisions with atoms and higher resistance.

Question 5

What instrument is used to measure the voltage across a component in a circuit?

Accepted Answer

Voltmeter

Answer

A voltmeter measures the potential difference (voltage) across a component and is connected in parallel with the component being measured. An ammeter measures current and is connected in series.

Mechanical Aptitude Test Practice Test

Mechanical Aptitude Test Practice Test

Mechanical Aptitude Basic Electrical Circuits Questions and Answers 3