IBEW Aptitude Test Mechanical Reasoning Principles Questions and Answers

Question 1

If gear X turns clockwise as shown by the arrow, which of the following statements is true about gears Y and Z? (Image depicts three meshed gears in a line: X, Y, Z)

Accepted Answer

Gear Y turns counter-clockwise and Gear Z turns clockwise.

Answer

Gear Y turns clockwise and Gear Z turns counter-clockwise.

Answer

Both Gear Y and Gear Z turn clockwise.

Answer

Both Gear Y and Gear Z turn counter-clockwise.

Question 2

An electrician needs to lift a heavy transformer weighing 200 lbs to the top of a utility pole. Which pulley system will require the least amount of effort (force) to lift the transformer?

Accepted Answer

A system with one fixed and one movable pulley.

Answer

A system with a single fixed pulley.

Answer

A system with two fixed pulleys.

Answer

Lifting the transformer by hand with a single rope.

Question 3

A worker is using a 6-foot long crowbar as a lever to move a heavy crate. The fulcrum is placed 1 foot from the end of the crowbar touching the crate. To move the crate, where should the worker apply force to achieve the maximum mechanical advantage?

Accepted Answer

At the very end of the crowbar, 5 feet from the fulcrum.

Answer

At the very end of the crowbar, 6 feet from the crate.

Answer

In the middle of the crowbar, 3 feet from the crate.

Answer

Directly next to the fulcrum.

Question 4

Water is being pumped through a pipe that narrows in the middle and then widens again. According to Bernoulli's principle, what happens to the water's speed and pressure in the narrow section compared to the wider sections?

Accepted Answer

The speed increases and the pressure decreases.

Answer

The speed decreases and the pressure increases.

Answer

Both the speed and the pressure increase.

Answer

Both the speed and the pressure decrease.

Question 5

Two gears are connected by a crossed drive belt. The drive gear (A) has a diameter of 10 inches and the driven gear (B) has a diameter of 5 inches. If gear A rotates clockwise, what is the motion of gear B?

Accepted Answer

Counter-clockwise at twice the speed of A.

Answer

Clockwise at half the speed of A.

Answer

Counter-clockwise at half the speed of A.

Answer

Clockwise at twice the speed of A.

Question 6

A fully loaded toolbox is easier to pull up a long, gradual ramp than to lift straight up to the same height. This is because the ramp:

Accepted Answer

Increases the distance over which the force is applied, reducing the required effort.

Answer

Decreases the total amount of work being done.

Answer

Eliminates the force of gravity on the toolbox.

Answer

Reduces the mass of the toolbox.