Mechanical Aptitude Ultimate Flashcards
7 cards from real MECHANICAL APTITUDE practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Mechanical Aptitude Ultimate flashcards as text
A lever has its fulcrum 1 foot from a 300 lb load and 3 feet from the effort point. How much effort is required to lift the load?
Answer: 100 lbs
By the law of levers: Effort × 3 = 300 × 1, so Effort = 300/3 = 100 lbs.
What is the function of a flywheel in an engine?
Answer: To store rotational energy and smooth out power pulses
A flywheel's mass and rotational inertia store energy during power strokes and release it during compression strokes, smoothing engine output.
Which type of bearing is most suitable for heavy radial loads at low speeds?
Answer: Roller bearing
Roller bearings have line contact instead of point contact, distributing the load over a larger area and handling heavier radial loads.
Air pressure in a sealed container is 30 PSI at 60°F. If the temperature rises to 120°F (in Rankine: 520R to 580R), what is the new pressure?
Answer: 33.5 PSI
Using Gay-Lussac's Law (P1/T1 = P2/T2 in Rankine): P2 = 30 × (580/520) ≈ 33.5 PSI.
A flat washer placed under a bolt head primarily serves to:
Answer: Distribute the clamping load over a larger area
A flat washer spreads the bolt's clamping force over a wider surface area, preventing the bolt head from pulling through soft or thin materials.
In a reciprocating piston engine, what converts the piston's linear motion into rotational motion?
Answer: Crankshaft
The crankshaft uses offset journals (throws) connected to connecting rods to convert the piston's up-and-down linear motion into rotation.
A spring with a spring constant of 50 lb/in is compressed 3 inches. How much energy is stored in the spring?
Answer: 225 in-lbs
Spring potential energy = ½ × k × x² = ½ × 50 × 3² = ½ × 50 × 9 = 225 in-lbs.