FCTC Test Applying Mechanical Reasoning Questions and Answers 3 — Questions and Answers
Question 1: A compound pulley system uses 4 rope segments supporting a load. If the load weighs 200 lbs, how much force is needed to lift it (ignoring friction)?
- 25 lbs
- 50 lbs (Correct answer)
- 100 lbs
- 200 lbs
Correct answer: 50 lbs
In a compound pulley with 4 supporting rope segments, the required force equals the load divided by the number of segments: 200 ÷ 4 = 50 lbs.
Question 2: Two gears are meshed together. Gear A has 12 teeth and Gear B has 36 teeth. If Gear A rotates at 90 RPM, at what speed does Gear B rotate?
- 270 RPM
- 90 RPM
- 45 RPM
- 30 RPM (Correct answer)
Correct answer: 30 RPM
Gear speed is inversely proportional to tooth count; Gear B rotates at 90 × (12/36) = 30 RPM.
Question 3: A worker uses a ramp 10 feet long to push a 300 lb crate up to a platform 2 feet high. Approximately how much force is required (ignoring friction)?
- 30 lbs
- 60 lbs (Correct answer)
- 150 lbs
- 300 lbs
Correct answer: 60 lbs
The mechanical advantage of a ramp equals length divided by height (10/2 = 5), so force needed = 300 ÷ 5 = 60 lbs.
Question 4: Which type of lever has the fulcrum located between the effort and the load?
- Second-class lever
- Third-class lever
- First-class lever (Correct answer)
- Compound lever
Correct answer: First-class lever
A first-class lever has the fulcrum between the effort and load, such as a seesaw or crowbar.
Question 5: A spring stretches 3 inches when a 6 lb weight is hung from it. How far will it stretch with a 10 lb weight?
- 3 inches
- 4 inches
- 5 inches (Correct answer)
- 6 inches
Correct answer: 5 inches
By Hooke's Law, stretch is proportional to force; 3 inches × (10/6) = 5 inches.
Question 6: A hydraulic press has an input piston of 2 sq in and an output piston of 20 sq in. If 50 lbs of force is applied to the input, what force is produced at the output?
- 5 lbs
- 50 lbs
- 500 lbs (Correct answer)
- 1000 lbs
Correct answer: 500 lbs
Pascal's principle: output force = input force × (output area / input area) = 50 × (20/2) = 500 lbs.
Question 7: A wrench handle is 12 inches long. A second wrench on the same bolt has a handle of 18 inches. Compared to the shorter wrench, the longer wrench produces how much more torque with the same force?
- 25% more
- 33% more
- 50% more (Correct answer)
- 75% more
Correct answer: 50% more
Torque = force × distance; 18/12 = 1.5, meaning the longer wrench produces 50% more torque.
FCTC Test Applying Mechanical Reasoning Questions and Answers 3
A compound pulley system uses 4 rope segments supporting a load.
If the load weighs 200 lbs, how much force is needed to lift it (ignoring friction)?