Bennett Mechanical Test Pulleys and Levers 2 — Questions and Answers
Question 1: A single fixed pulley is used to raise a load. What is its main advantage?
- It changes the direction of the applied force (Correct answer)
- It reduces the force needed by half
- It doubles the speed of lifting
- It eliminates friction entirely
Correct answer: It changes the direction of the applied force
A single fixed pulley provides no mechanical advantage but lets you pull down to lift up, changing force direction.
Question 2: In a first-class lever, where is the fulcrum located?
- Between the effort and the load (Correct answer)
- At the same point as the load
- Beyond the load
- Outside the lever arm
Correct answer: Between the effort and the load
A first-class lever has the fulcrum positioned between the effort and the load, like a seesaw.
Question 3: A load is 4 ft from the fulcrum and the effort is applied 12 ft from the fulcrum. What is the mechanical advantage?
- 3 (Correct answer)
- 4
- 12
- 0.33
Correct answer: 3
Mechanical advantage equals effort arm divided by load arm, so 12 ÷ 4 = 3.
Question 4: A system of pulleys has 4 supporting rope segments lifting a load. What is the ideal mechanical advantage?
- 4 (Correct answer)
- 2
- 8
- 1
Correct answer: 4
The ideal mechanical advantage of a block and tackle equals the number of rope segments supporting the load.
Question 5: Which type of lever has the load between the fulcrum and the effort?
- Second-class lever (Correct answer)
- First-class lever
- Third-class lever
- Compound lever
Correct answer: Second-class lever
A second-class lever, like a wheelbarrow, has the load between the fulcrum and the effort.
Question 6: To lift a 200 lb load with a mechanical advantage of 4, how much effort force is required (ignoring friction)?
- 50 lb (Correct answer)
- 100 lb
- 200 lb
- 800 lb
Correct answer: 50 lb
Effort equals load divided by mechanical advantage, so 200 ÷ 4 = 50 lb.
Question 7: When a movable pulley is used, what happens to the distance the rope must be pulled compared to the load's rise?
- The rope is pulled twice as far (Correct answer)
- The rope is pulled half as far
- The rope and load move equally
- The rope does not move
Correct answer: The rope is pulled twice as far
A movable pulley halves the force but requires pulling twice the length of rope as the load rises.
Bennett Mechanical Test Pulleys and Levers 2
A single fixed pulley is used to raise a load.
What is its main advantage?