EIAT Gears, Pulleys, and Levers 2 — Questions and Answers
Question 1: A gear with 48 teeth meshes with a gear with 16 teeth. If the smaller gear rotates at 900 RPM, what is the speed of the larger gear?
- 150 RPM
- 300 RPM (Correct answer)
- 1800 RPM
- 2700 RPM
Correct answer: 300 RPM
Gear ratio is 48:16 = 3:1, so the larger gear turns at 900 ÷ 3 = 300 RPM.
Question 2: In a compound pulley system with 4 rope segments supporting the load, what is the mechanical advantage?
- 2
- 3
- 4 (Correct answer)
- 8
Correct answer: 4
The mechanical advantage of a compound pulley equals the number of rope segments supporting the moving block.
Question 3: A first-class lever has the fulcrum between the effort and the load. Which everyday tool is an example?
- Wheelbarrow
- Nutcracker
- Seesaw (Correct answer)
- Shovel
Correct answer: Seesaw
A seesaw has the fulcrum in the middle with effort and load on opposite ends, making it a first-class lever.
Question 4: When two gears mesh, they always rotate in:
- The same direction
- Opposite directions (Correct answer)
- Alternating directions
- The same direction at the same speed
Correct answer: Opposite directions
Meshing gears always rotate in opposite directions because the teeth interlock and push against each other.
Question 5: A load of 200 lb is placed 2 feet from the fulcrum. How much effort is needed 8 feet from the fulcrum on the other side to balance it?
- 25 lb
- 50 lb (Correct answer)
- 100 lb
- 400 lb
Correct answer: 50 lb
Using lever balance: 200 × 2 = Effort × 8, so Effort = 400 ÷ 8 = 50 lb.
Question 6: A fixed pulley changes the direction of force but provides a mechanical advantage of:
- 0
- 1 (Correct answer)
- 2
- Depends on rope length
Correct answer: 1
A single fixed pulley only redirects the force; it provides a mechanical advantage of exactly 1.
Question 7: If a gear train consists of gears with 10, 20, and 40 teeth in series, what is the overall gear ratio from first to last?
- 1:2
- 1:4 (Correct answer)
- 1:8
- 2:1
Correct answer: 1:4
The overall ratio is (20/10) × (40/20) = 2 × 2 = 4, so the output gear turns at 1/4 the input speed (1:4).
EIAT Gears, Pulleys, and Levers 2
A gear with 48 teeth meshes with a gear with 16 teeth.
If the smaller gear rotates at 900 RPM, what is the speed of the larger gear?