FCTC FCTC Test Pulleys, Gears, and Levers Questions and Answers 4 — Questions and Answers
Question 1: If you double the length of the effort arm of a lever while keeping the resistance arm the same, what happens to the mechanical advantage?
- It stays the same
- It doubles (Correct answer)
- It is cut in half
- It quadruples
Correct answer: It doubles
Since MA = effort arm ÷ resistance arm, doubling the effort arm doubles the mechanical advantage.
Question 2: A block-and-tackle system has 3 movable pulleys. Approximately how many rope segments support the load?
- 2
- 3
- 6 (Correct answer)
- 9
Correct answer: 6
Each movable pulley adds 2 supporting rope segments, so 3 movable pulleys create 6 supporting segments.
Question 3: In a gear system, which gear rotates faster — the one with more teeth or fewer teeth?
- More teeth
- Fewer teeth (Correct answer)
- They rotate at the same speed
- It depends on the direction of rotation
Correct answer: Fewer teeth
The gear with fewer teeth rotates faster because fewer teeth must mesh per revolution of the larger gear.
Question 4: A pair of scissors is an example of which type of simple machine?
- Second-class lever
- First-class lever (Correct answer)
- Third-class lever
- Fixed pulley
Correct answer: First-class lever
Scissors are first-class levers because the fulcrum (pivot) is between the effort (handles) and the load (blades cutting).
Question 5: A movable pulley has a mechanical advantage of 2. If the load is 300 lbs, how far must the effort rope be pulled to raise the load 1 foot?
- 0.5 feet
- 1 foot
- 2 feet (Correct answer)
- 3 feet
Correct answer: 2 feet
When MA = 2, the effort distance is twice the load distance, so you must pull 2 feet of rope to lift the load 1 foot.
Question 6: What term describes the ratio of output force to input force in a simple machine?
- Velocity ratio
- Mechanical advantage (Correct answer)
- Efficiency
- Torque
Correct answer: Mechanical advantage
Mechanical advantage is defined as the ratio of output (resistance) force to input (effort) force.
Question 7: A rack and pinion converts which type of motion?
- Rotary to rotary
- Linear to rotary (or vice versa) (Correct answer)
- Oscillating to linear
- Reciprocating to oscillating
Correct answer: Linear to rotary (or vice versa)
A rack and pinion converts rotational motion of the pinion gear into linear motion of the rack, or vice versa.
FCTC FCTC Test Pulleys, Gears, and Levers Questions and Answers 4
If you double the length of the effort arm of a lever while keeping the resistance arm the same, what happens to the mechanical advantage?