FCTC Test Pulleys, Gears, and Levers Questions and Answers 4 — Questions and Answers
Question 1: A movable pulley is attached to a 200 lb load, and a fixed pulley redirects the rope. How much effort is required to lift the load (ignore friction)?
- 50 lbs
- 100 lbs (Correct answer)
- 150 lbs
- 200 lbs
Correct answer: 100 lbs
A movable pulley provides a mechanical advantage of 2, so the required effort is 200 ÷ 2 = 100 lbs.
Question 2: A large driving gear has 48 teeth and turns a small gear with 12 teeth. How would you describe the output of the small gear compared to the input?
- Lower speed, greater torque
- Higher speed, less torque (Correct answer)
- Same speed, same torque
- Higher speed, greater torque
Correct answer: Higher speed, less torque
When a large gear drives a smaller gear, the smaller gear spins faster but produces less torque.
Question 3: A lever's mechanical advantage is calculated as:
- Load arm length ÷ Effort arm length
- Effort arm length ÷ Load arm length (Correct answer)
- Load × Effort
- Fulcrum distance × Load
Correct answer: Effort arm length ÷ Load arm length
Mechanical advantage of a lever = Effort arm length ÷ Load arm length, indicating how much force is multiplied.
Question 4: In a block-and-tackle system with 3 movable pulleys and 3 fixed pulleys, what is the maximum mechanical advantage possible?
- 3
- 4
- 6 (Correct answer)
- 9
Correct answer: 6
With 3 movable pulleys the mechanical advantage equals the number of rope segments supporting the load, which is 6.
Question 5: Three gears are arranged in a line: A drives B, and B drives C. Gears A and C will rotate in which direction relative to each other?
- Opposite directions
- The same direction (Correct answer)
- C does not rotate
- It depends on their sizes
Correct answer: The same direction
With three gears in a series (A→B→C), an odd number of gear meshes means the first and last gear rotate in the same direction.
Question 6: A crowbar (first-class lever) is used to pry open a crate. The fulcrum is placed 4 inches from the load and the firefighter pushes down 32 inches from the fulcrum. What is the mechanical advantage?
- 4
- 6
- 8 (Correct answer)
- 10
Correct answer: 8
MA = Effort arm ÷ Load arm = 32 ÷ 4 = 8, meaning the firefighter multiplies their force by 8.
Question 7: When using a pulley system, if the effort rope is pulled 6 feet to raise a load, but the load only rises 1 foot, what is the mechanical advantage?
- 1
- 3
- 6 (Correct answer)
- 12
Correct answer: 6
Mechanical advantage = distance effort moves ÷ distance load moves = 6 ÷ 1 = 6.
FCTC Test Pulleys, Gears, and Levers Questions and Answers 4
A movable pulley is attached to a 200 lb load, and a fixed pulley redirects the rope.
How much effort is required to lift the load (ignore friction)?