WTMA Levers, Pulleys, and Gears 3 — Questions and Answers
Question 1: A fishing rod is an example of which class of lever?
- First class
- Second class
- Third class (Correct answer)
- None of the above
Correct answer: Third class
A fishing rod is a third-class lever — the effort (hand) is between the fulcrum (base hand) and the load (fish).
Question 2: If a movable pulley is used (with one fixed pulley redirecting the rope), how many rope segments support the load?
- 1
- 2 (Correct answer)
- 3
- 4
Correct answer: 2
A movable pulley supported by a rope that also passes through a fixed redirecting pulley has 2 rope segments supporting the load.
Question 3: A driver gear with 30 teeth turns a driven gear with 15 teeth. The output gear rotates:
- At half the speed with more torque
- At double the speed with less torque (Correct answer)
- At the same speed
- At double the speed with more torque
Correct answer: At double the speed with less torque
Fewer teeth on the driven gear means it spins faster but produces less torque than the driver.
Question 4: An effort of 60 lb is applied 5 feet from the fulcrum on a first-class lever. What load can be balanced 3 feet from the fulcrum on the other side?
- 36 lb
- 100 lb (Correct answer)
- 180 lb
- 300 lb
Correct answer: 100 lb
Effort × 5 = Load × 3 → 300 = Load × 3 → Load = 100 lb.
Question 5: Which of the following best describes mechanical advantage?
- The total weight a machine can lift
- The ratio of output force to input force (Correct answer)
- The speed at which a machine operates
- The energy lost to friction
Correct answer: The ratio of output force to input force
Mechanical advantage is the ratio of the output force (load) to the input force (effort).
Question 6: In a compound pulley system, increasing the number of rope segments supporting the load will:
- Increase the effort required
- Decrease the effort required but increase the rope pulled (Correct answer)
- Decrease both effort and rope pulled
- Have no effect on effort
Correct answer: Decrease the effort required but increase the rope pulled
More rope segments reduce the required effort but mean you must pull a longer length of rope to raise the load.
Question 7: A spur gear train has three gears in a row: A drives B, and B drives C. Gears A and C rotate in:
- Opposite directions
- The same direction (Correct answer)
- Random directions depending on size
- Neither rotates if B is in the middle
Correct answer: The same direction
Each gear reverses direction; with three gears (odd number), gears A and C rotate in the same direction.
WTMA Levers, Pulleys, and Gears 3
A fishing rod is an example of which class of lever?