CBST Mechanical Reasoning Flashcards

In a hydraulic system, a small piston with a 1 sq inch area pushes fluid to a large piston with a 10 sq inch area. If 50 lbs of force is applied to the small piston, how much force does the large piston exert?

Answer: 500 pounds

Pascal's principle states force is multiplied proportionally to the area ratio: 50 × (10/1) = 500 pounds.

A bolt with fine threads requires more turns to tighten than one with coarse threads. What is the advantage of fine threads?

Answer: Greater mechanical advantage and holding strength

Fine threads have a smaller pitch (distance per revolution), acting like a longer inclined plane to provide greater mechanical advantage and clamping force.

When a car rounds a curve, passengers feel pushed outward. What causes this sensation?

Answer: Inertia resisting the change in direction

This is inertia — the passengers' bodies tend to continue in a straight line while the car changes direction.

A circuit has two 6-ohm resistors connected in parallel. What is the total resistance?

Answer: 3 ohms

For two equal resistors in parallel, the total resistance is half of one resistor's value: 6 ÷ 2 = 3 ohms.

Which tool would be BEST for measuring the inside diameter of a cylindrical pipe?

Answer: Inside calipers

Inside calipers are specifically designed to measure the internal dimensions of holes, pipes, and cavities.

A refrigerator works by circulating a refrigerant. What happens when the refrigerant evaporates inside the refrigerator?

Answer: It absorbs heat, cooling the interior

Evaporation is an endothermic process — the refrigerant absorbs heat energy from the refrigerator's interior as it changes from liquid to gas.