FCTC FREE FCTC Test Mechanical Reasoning Principles Questions and Answers 2 — Questions and Answers
Question 1: A hydraulic jack uses a small piston with an area of 2 sq in and a large piston with an area of 20 sq in. If you apply 50 lbs of force to the small piston, how much force is exerted by the large piston?
- 500 lbs (Correct answer)
- 250 lbs
- 100 lbs
- 1000 lbs
Correct answer: 500 lbs
Pascal's law states that pressure is transmitted equally, so force output equals input force multiplied by the ratio of piston areas (50 × 20/2 = 500 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, how fast does Gear B rotate?
- 30 RPM (Correct answer)
- 270 RPM
- 45 RPM
- 108 RPM
Correct answer: 30 RPM
The gear speed ratio is inverse to the tooth count ratio, so Gear B rotates at 90 × (12/36) = 30 RPM.
Question 3: A lever has its fulcrum 1 foot from a 300-lb load and 4 feet from where force is applied. How much effort force is needed to lift the load?
- 75 lbs (Correct answer)
- 1200 lbs
- 150 lbs
- 300 lbs
Correct answer: 75 lbs
Using the lever principle, effort × effort arm = load × load arm, so effort = 300 × 1 / 4 = 75 lbs.
Question 4: A pulley system has one fixed pulley and one movable pulley. What is the mechanical advantage of this system?
- 2 (Correct answer)
- 1
- 4
- 3
Correct answer: 2
A system with one fixed and one movable pulley has a mechanical advantage of 2, meaning you lift with half the load's weight.
Question 5: Which type of simple machine is an inclined plane wrapped around a cylinder?
- Screw (Correct answer)
- Wedge
- Lever
- Wheel and axle
Correct answer: Screw
A screw is essentially an inclined plane wrapped helically around a cylinder, converting rotational force into linear motion.
Question 6: A wrench 12 inches long applies 20 lbs of force perpendicular to a bolt. What torque is applied to the bolt?
- 240 in-lbs (Correct answer)
- 20 in-lbs
- 32 in-lbs
- 120 in-lbs
Correct answer: 240 in-lbs
Torque equals force multiplied by the perpendicular distance (moment arm), so torque = 20 lbs × 12 in = 240 in-lbs.
FCTC FREE FCTC Test Mechanical Reasoning Principles Questions and Answers 2
A hydraulic jack uses a small piston with an area of 2 sq in and a large piston with an area of 20 sq in.
If you apply 50 lbs of force to the small piston, how much force is exerted by the large piston?