Pulleys and Levers Flashcards
7 cards from real Bennett Mechanical Test practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Pulleys and Levers flashcards as text
A crowbar used to pry up a board with the curved end resting on the ground is which lever class?
Answer: First-class lever
A prying crowbar has the fulcrum between the effort and the load, making it a first-class lever.
A movable pulley system reduces the lifting force to one-third. How many rope segments support the load?
Answer: 3
Reducing force to one-third means a mechanical advantage of 3, which equals 3 supporting rope segments.
Using a 6 ft lever with the fulcrum 1 ft from the load, what is the maximum mechanical advantage?
Answer: 5
Effort arm is 5 ft and load arm is 1 ft, so mechanical advantage is 5 ÷ 1 = 5.
A pair of tweezers used to grip a small object is which lever class?
Answer: Third-class lever
Tweezers are third-class levers because the effort is applied between the fulcrum and the load.
Why does a single fixed pulley have a mechanical advantage of 1?
Answer: Only one rope segment supports the load
A fixed pulley has just one rope segment supporting the load, so it offers no force multiplication.
Two children balance a seesaw. The heavier child should sit:
Answer: Closer to the fulcrum
The heavier child must sit closer to the fulcrum so the moments on both sides are equal.
An effort of 25 lb lifts a 150 lb load using a pulley system. What is the mechanical advantage?
Answer: 6
Mechanical advantage equals load divided by effort, so 150 ÷ 25 = 6.