CPS Mechanical Aptitude and Principles 2 — Questions and Answers
Question 1: Two gears are meshed together. If the driving gear has 10 teeth and the driven gear has 30 teeth, how does the driven gear turn compared to the driver?
- Three times faster
- Three times slower (Correct answer)
- At the same speed
- In the same direction
Correct answer: Three times slower
A larger driven gear turns slower in proportion to its tooth count, so 30/10 means it turns three times slower.
Question 2: A first-class lever has the fulcrum located where?
- Between the effort and the load (Correct answer)
- At the load end
- At the effort end
- Outside both the effort and load
Correct answer: Between the effort and the load
In a first-class lever, like a seesaw, the fulcrum sits between the effort and the load.
Question 3: Which simple machine is a doorknob an example of?
- Pulley
- Wheel and axle (Correct answer)
- Inclined plane
- Wedge
Correct answer: Wheel and axle
A doorknob turns a small shaft (axle) using a larger wheel, making it a wheel and axle.
Question 4: If you increase the length of a ramp while keeping the same height, what happens to the effort needed to push a load up it?
- It increases
- It decreases (Correct answer)
- It stays the same
- It drops to zero
Correct answer: It decreases
A longer ramp reduces the slope, decreasing the effort required to move the load up.
Question 5: In a hydraulic system, pressure applied to a confined fluid is transmitted how?
- Only downward
- Only in the direction of the force
- Equally in all directions (Correct answer)
- It weakens with distance
Correct answer: Equally in all directions
Pascal's principle states that pressure on a confined fluid is transmitted equally in all directions.
Question 6: A fixed pulley attached to a ceiling primarily changes what?
- The amount of force needed
- The direction of the force (Correct answer)
- The weight of the load
- The speed of gravity
Correct answer: The direction of the force
A single fixed pulley changes the direction of the applied force but does not reduce the effort needed.
Question 7: Which material would conduct heat fastest, an important factor for firefighters handling tools?
- Wood
- Rubber
- Copper (Correct answer)
- Plastic
Correct answer: Copper
Copper is a metal and an excellent heat conductor compared to insulators like wood, rubber, or plastic.