CPS CPS Firefighter Test Mechanical Aptitude and Principles Questions and Answers 2 — Questions and Answers
Question 1: A firefighter needs to move a heavy hose reel using a lever. If the effort arm is 4 feet and the load arm is 1 foot, what is the mechanical advantage?
- 1
- 2
- 4 (Correct answer)
- 8
Correct answer: 4
Mechanical advantage of a lever equals effort arm length divided by load arm length: 4 ÷ 1 = 4.
Question 2: Water flows through a 4-inch diameter pipe and enters a 2-inch diameter pipe. How does the water velocity change?
- It decreases by half
- It stays the same
- It quadruples (Correct answer)
- It doubles
Correct answer: It quadruples
When pipe diameter is halved, the cross-sectional area decreases by a factor of 4, so velocity quadruples to maintain constant flow rate.
Question 3: Which type of pulley system provides a mechanical advantage greater than 1 by using multiple sheaves?
- Fixed pulley
- Block and tackle (Correct answer)
- Single movable pulley
- Wheel and axle
Correct answer: Block and tackle
A block and tackle system uses multiple pulleys to multiply force, providing a mechanical advantage proportional to the number of rope segments supporting the load.
Question 4: A firefighter climbs a ladder leaning against a building. As the ladder angle decreases (becomes more horizontal), the force at the base of the ladder:
- Decreases
- Remains constant
- Increases (Correct answer)
- Reverses direction
Correct answer: Increases
As a ladder becomes more horizontal, the horizontal thrust at the base increases because more force is directed outward rather than downward.
Question 5: In a hydraulic system, a small piston with area 2 sq in applies 100 lbs of force. What force does a large piston with area 10 sq in exert?
- 20 lbs
- 100 lbs
- 200 lbs
- 500 lbs (Correct answer)
Correct answer: 500 lbs
Pascal's Law states pressure is equal throughout; pressure = 100/2 = 50 psi, so force on large piston = 50 × 10 = 500 lbs.
Question 6: A gear with 12 teeth drives a gear with 36 teeth. If the drive gear rotates at 90 RPM, what is the speed of the driven gear?
- 10 RPM
- 30 RPM (Correct answer)
- 90 RPM
- 270 RPM
Correct answer: 30 RPM
Gear ratio = 36/12 = 3, so the driven gear rotates at 90 ÷ 3 = 30 RPM.
CPS CPS Firefighter Test Mechanical Aptitude and Principles Questions and Answers 2
A firefighter needs to move a heavy hose reel using a lever.
If the effort arm is 4 feet and the load arm is 1 foot, what is the mechanical advantage?