Mechanical Aptitude Mechanical Aptitude Levers, Pulleys, and Gears Questions and Answers 2

Question 1

A worker uses a 4-foot crowbar to pry up a heavy crate, placing the fulcrum 1 foot from the load end. If the crate weighs 200 pounds, approximately how much force must the worker apply at the other end?

Accepted Answer

About 67 pounds

Answer

With the fulcrum 1 foot from the load, the effort arm is 3 feet, so the mechanical advantage is 3:1, meaning roughly 67 pounds of effort moves 200 pounds.

Question 2

In a compound pulley system with 4 supporting ropes, how much force is theoretically needed to lift a 400-pound load?

Accepted Answer

100 pounds

Answer

A compound pulley with 4 supporting ropes provides a mechanical advantage of 4, so 400 divided by 4 equals 100 pounds of effort.

Question 3

Two meshed gears have 20 teeth and 60 teeth respectively. If the smaller gear rotates at 300 RPM, how fast does the larger gear turn?

Accepted Answer

100 RPM

Answer

The gear ratio is 60:20 or 3:1, so the larger gear turns at 300 divided by 3, which equals 100 RPM.

Question 4

Which class of lever has the effort applied between the fulcrum and the load?

Accepted Answer

Third-class lever

Answer

A third-class lever places the effort between the fulcrum and the load, such as a pair of tweezers or a fishing rod.

Question 5

A fixed pulley is attached to a ceiling and used to lift a 50-pound box. What is the primary advantage of this setup?

Accepted Answer

It changes the direction of the force so you can pull downward

Answer

A single fixed pulley provides no mechanical advantage but allows you to pull downward using your body weight instead of lifting upward.

Mechanical Aptitude Test Practice Test

Mechanical Aptitude Test Practice Test

Mechanical Aptitude Mechanical Aptitude Levers, Pulleys, and Gears Questions and Answers 2