ASVAB (Armed Services Vocational Aptitude Battery)Paragraph Comprehension (PC)Hard
Read the following passage: "The principle of leverage is fundamental in mechanics, allowing a small force to move a much larger load. A lever consists of a rigid bar that pivots around a fixed point called a fulcrum. There are three classes of levers, determined by the relative positions of the fulcrum, the effort (the applied force), and the load (the resistance being moved). In a first-class lever, the fulcrum is located between the effort and the load, like a seesaw or crowbar. A second-class lever has the load between the fulcrum and the effort, as seen in a wheelbarrow. Finally, a third-class lever has the effort applied between the fulcrum and the load, exemplified by tweezers or a fishing rod. Each class offers different advantages in terms of mechanical advantage and range of motion." A person uses a wheelbarrow to move a pile of dirt. Which class of lever is best represented by this action?
- ASecond-class lever
- BThird-class lever
- CFirst-class lever
- DNot a lever
Show answer & explanationAnswer & explanation
Correct answer: A. Second-class lever
The passage explicitly states: 'A second-class lever has the load between the fulcrum and the effort, as seen in a wheelbarrow.' This directly identifies the wheelbarrow as a second-class lever.
Why the other options are wrong
- B. Third-class levers have the effort in the middle (e.g., tweezers).
- C. First-class levers have the fulcrum in the middle (e.g., seesaw).
- D. The passage clearly identifies a wheelbarrow as a type of lever.
Second-Class Lever
A type of lever where the load is positioned between the fulcrum and the effort.
- Load is central.
- Always provides mechanical advantage (>1).
- Examples: wheelbarrow, nutcracker, bottle opener.
Memory trick: FLE 123: Fulcrum, Load, Effort.