Firefighter Tools and Mechanical Reasoning 2 — Questions and Answers
Question 1: Two gears are meshed together. If the driver gear turns clockwise, which way does the meshed driven gear turn?
- Clockwise
- Counterclockwise (Correct answer)
- It does not turn
- Both directions alternately
Correct answer: Counterclockwise
Two directly meshed gears always rotate in opposite directions.
Question 2: A firefighter uses a longer pry bar to lift a heavy beam. What does the longer handle primarily increase?
- The weight of the beam
- The mechanical advantage (Correct answer)
- The friction on the floor
- The beam's density
Correct answer: The mechanical advantage
A longer lever arm increases mechanical advantage, making the load easier to move.
Question 3: Which tool is best suited for forcing open an inward-swinging door during a fire rescue?
- Halligan bar (Correct answer)
- Pipe wrench
- Tin snips
- Caulk gun
Correct answer: Halligan bar
The Halligan bar is a standard forcible-entry tool designed to pry, twist, and punch through doors.
Question 4: In a pulley system with two supporting rope segments, lifting a 100 lb load ideally requires how much input force (ignoring friction)?
- 200 lb
- 100 lb
- 50 lb (Correct answer)
- 25 lb
Correct answer: 50 lb
Two supporting rope segments halve the required force, so 100 lb needs about 50 lb of input.
Question 5: Water flows through a hose that narrows at the nozzle. What happens to the water's velocity at the narrow point?
- It decreases
- It increases (Correct answer)
- It stays the same
- It stops
Correct answer: It increases
When a fluid passes through a smaller opening, its velocity increases to maintain flow.
Question 6: A screw is an example of which simple machine wrapped around a cylinder?
- Lever
- Pulley
- Inclined plane (Correct answer)
- Wheel and axle
Correct answer: Inclined plane
A screw is essentially an inclined plane wound around a central shaft.
Question 7: Which property of a metal ladder makes it dangerous to use near electrical lines?
- It conducts electricity (Correct answer)
- It floats on water
- It melts easily
- It rusts quickly
Correct answer: It conducts electricity
Metal is an electrical conductor, so a metal ladder can transmit current to the user.
Firefighter Tools and Mechanical Reasoning 2
Two gears are meshed together.
If the driver gear turns clockwise, which way does the meshed driven gear turn?