FireTEAM Mechanical Aptitude 1 — Questions and Answers
Question 1: Which of the following tools uses a wedge to perform its function?
- Screwdriver
- Pliers
- Hammer
- Axe (Correct answer)
Correct answer: Axe
An axe is a classic example of a tool that utilizes a wedge. Its blade is designed as a wedge, which, when driven into material like wood, applies concentrated force to split it apart. This simple machine principle allows the axe to efficiently overcome resistance and perform its cutting or splitting function.
Question 2: If a pulley system has two wheels and the rope is looped around both, what is the mechanical advantage of this system?
- 1
- 2 (Correct answer)
- 3
- 4
Correct answer: 2
The mechanical advantage of a pulley system is generally determined by the number of rope segments directly supporting the movable load. In a system with two wheels where the rope is looped around both, there are typically two segments of rope supporting the load. This configuration effectively halves the effort required to lift the load, providing a mechanical advantage of 2.
Question 3: A fire hose is connected to a hydrant. If you want to increase the water pressure from the hydrant, which of the following actions should you take?
- Increase the diameter of the hose.
- Decrease the diameter of the hose. (Correct answer)
- Lower the height of the hose relative to the hydrant.
- Use a longer hose.
Correct answer: Decrease the diameter of the hose.
According to the principle of continuity in fluid dynamics, for a constant flow rate, decreasing the cross-sectional area (diameter) of a hose will increase the velocity of the water. This increase in velocity, in turn, leads to an increase in dynamic pressure within the hose. Therefore, using a narrower hose will increase the water pressure from the hydrant.
Question 4: Which gear system will make the driven gear spin faster than the driver gear?
- A small driver gear connected to a large driven gear.
- A large driver gear connected to a small driven gear. (Correct answer)
- Two gears of the same size connected together.
- A driver gear with no connection to a driven gear.
Correct answer: A large driver gear connected to a small driven gear.
To make the driven gear spin faster than the driver gear, the driver gear must be larger than the driven gear. This configuration creates a gear reduction in torque but an increase in rotational speed for the smaller driven gear. Each rotation of the large driver gear causes the smaller driven gear to complete multiple rotations, thus increasing its speed.
Question 5: If you use a lever to lift a heavy object and the fulcrum is closer to the load than to the effort, what happens?
- The load will be harder to lift
- The load will be easier to lift. (Correct answer)
- The load will lift at the same ease as the effort.
- The lever will not work in this configuration.
Correct answer: The load will be easier to lift.
When the fulcrum is positioned closer to the load than to the effort, it creates a longer effort arm. This setup increases the mechanical advantage of the lever, meaning you need to apply less force (effort) over a greater distance to lift the heavy object. Consequently, the load becomes easier to lift.
FireTEAM Mechanical Aptitude 1
Which of the following tools uses a wedge to perform its function?