OAR Mechanical Comprehension: Electricity Questions and Answers

Question 1

A simple circuit consists of a battery and three light bulbs connected in series. If the middle bulb's filament breaks, what will happen to the other two bulbs?

Accepted Answer

They will both go out.

Answer

They will both get brighter.

Answer

The first bulb will stay lit, but the last one will go out.

Answer

They will both get dimmer, but stay lit.

Question 2

According to Ohm's Law, if the voltage in a circuit is doubled while the resistance remains constant, what is the effect on the current?

Accepted Answer

It is doubled.

Answer

It is halved.

Answer

It is quadrupled.

Answer

It remains the same.

Question 3

The wiring in a house allows a lamp in one room to be on while a television in another room is off. This indicates that the house's circuits are wired in which configuration?

Accepted Answer

A parallel circuit

Answer

A series circuit

Answer

A short circuit

Answer

An open circuit

Question 4

Which of the following best describes the primary function of a fuse in an electrical circuit?

Accepted Answer

To protect the circuit from excessive current.

Answer

To increase the voltage for connected devices.

Answer

To store a small amount of electrical charge.

Answer

To convert direct current (DC) to alternating current (AC).

Question 5

An electrical device uses 600 watts of power when connected to a 120-volt source. What is the current flowing through the device?

Accepted Answer

5 amperes

Answer

2 amperes

Answer

72,000 amperes

Answer

0.2 amperes

Question 6

Which of the following materials is the best electrical insulator, meaning it most effectively resists the flow of electricity?

Accepted Answer

Rubber

Answer

Copper

Answer

Aluminum

Answer

Sea water