FREE FCTC Test Mechanical Reasoning Principles Questions and Answers Flashcards

A 200-lb barrel is rolled up a 15-foot ramp to a platform 5 feet high. Ignoring friction, what is the force required?

Answer: 67 lbs

Force = Weight × (Height ÷ Ramp length) = 200 × (5 ÷ 15) ≈ 67 lbs.

Which factor does NOT affect the period (time for one oscillation) of a simple pendulum?

Answer: Mass of the bob

The period of a simple pendulum depends only on its length and gravity (T = 2π√(L/g)); mass has no effect.

A flat belt drive connects two pulleys. The driving pulley has a 6-inch radius and turns at 300 RPM. The driven pulley has a 2-inch radius. What is its speed?

Answer: 900 RPM

Belt speed is constant: driving speed × radius = driven speed × radius; 300 × 6 = N × 2, so N = 900 RPM.

A nail is driven into wood using a hammer. The hammer head exerts a large force over a very short time. This is an example of what mechanical concept?

Answer: Impulse-momentum

Impulse (force × time) equals the change in momentum; a large, brief force delivers high impulse to drive the nail.

In a series circuit with a 12V battery and three 4-ohm resistors, what is the total current?

Answer: 1 A

Total resistance = 4 + 4 + 4 = 12 ohms; Current = Voltage ÷ Resistance = 12 ÷ 12 = 1 A.

A machine has a mechanical efficiency of 80% and a mechanical advantage of 5. If you apply 40 lbs input force, what is the actual output force?

Answer: 160 lbs

Ideal output = 40 × 5 = 200 lbs; actual output = 200 × 0.80 = 160 lbs due to 80% efficiency.

Which property of a material describes its ability to return to its original shape after a deforming force is removed?

Answer: Elasticity

Elasticity is the property that allows a material to recover its original shape after stress is removed.