Mechanical Aptitude Mechanical Aptitude Levers, Pulleys, and Gears 2 — Questions and Answers
Question 1: A wheelbarrow is an example of which class of lever?
- First class
- Second class (Correct answer)
- Third class
- Fourth class
Correct answer: Second class
A wheelbarrow is a second-class lever because the load is between the fulcrum (wheel) and the effort (handles).
Question 2: Two gears are meshed together. Gear A has 40 teeth and Gear B has 10 teeth. If Gear A rotates at 100 RPM, how fast does Gear B rotate?
- 25 RPM
- 400 RPM (Correct answer)
- 250 RPM
- 40 RPM
Correct answer: 400 RPM
Speed ratio is inversely proportional to tooth count: Gear B speed = (40/10) × 100 = 400 RPM.
Question 3: A fixed pulley changes the _______ of a force but not the _______ required.
- magnitude; direction
- direction; magnitude (Correct answer)
- speed; effort
- load; fulcrum
Correct answer: direction; magnitude
A fixed pulley only redirects the force (direction), providing no mechanical advantage — the effort equals the load.
Question 4: On a lever, if the effort arm is 3 feet and the resistance arm is 1 foot, what is the mechanical advantage?
- 0.33
- 1
- 3 (Correct answer)
- 9
Correct answer: 3
Mechanical advantage = effort arm ÷ resistance arm = 3 ÷ 1 = 3.
Question 5: In a compound pulley system with 4 rope segments supporting the load, what is the mechanical advantage?
- 1
- 2
- 4 (Correct answer)
- 8
Correct answer: 4
In a block-and-tackle system, the mechanical advantage equals the number of rope segments that support the moving pulley.
Question 6: A driver gear with 20 teeth meshes with a driven gear with 60 teeth. The gear ratio is:
- 3:1 (speed increase)
- 1:3 (speed reduction) (Correct answer)
- 1:1 (no change)
- 2:3 (partial reduction)
Correct answer: 1:3 (speed reduction)
Gear ratio = driven teeth ÷ driver teeth = 60 ÷ 20 = 3:1 speed reduction (torque increases).
Question 7: Which lever class has the effort applied between the fulcrum and the load?
- First class
- Second class
- Third class (Correct answer)
- All classes
Correct answer: Third class
In a third-class lever, the effort is applied between the fulcrum and the load, providing speed and range of motion but no mechanical advantage greater than 1.
Mechanical Aptitude Mechanical Aptitude Levers, Pulleys, and Gears 2
A wheelbarrow is an example of which class of lever?