FCTC FREE FCTC Test Mechanical Reasoning Principles Questions and Answers 5 โ Questions and Answers
Question 1: A 200-lb barrel is rolled up a 15-foot ramp to a platform 5 feet high. Ignoring friction, what is the force required?
- 33 lbs
- 50 lbs
- 67 lbs (Correct answer)
- 100 lbs
Correct answer: 67 lbs
Force = Weight ร (Height รท Ramp length) = 200 ร (5 รท 15) โ 67 lbs.
Question 2: Which factor does NOT affect the period (time for one oscillation) of a simple pendulum?
- Length of the pendulum
- Gravitational acceleration
- Mass of the bob (Correct answer)
- All of the above affect the period
Correct answer: Mass of the bob
The period of a simple pendulum depends only on its length and gravity (T = 2ฯโ(L/g)); mass has no effect.
Question 3: 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?
- 100 RPM
- 300 RPM
- 600 RPM
- 900 RPM (Correct answer)
Correct answer: 900 RPM
Belt speed is constant: driving speed ร radius = driven speed ร radius; 300 ร 6 = N ร 2, so N = 900 RPM.
Question 4: 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?
- Torque
- Impulse-momentum (Correct answer)
- Mechanical advantage
- Centripetal force
Correct answer: Impulse-momentum
Impulse (force ร time) equals the change in momentum; a large, brief force delivers high impulse to drive the nail.
Question 5: In a series circuit with a 12V battery and three 4-ohm resistors, what is the total current?
- 0.5 A
- 1 A (Correct answer)
- 3 A
- 9 A
Correct answer: 1 A
Total resistance = 4 + 4 + 4 = 12 ohms; Current = Voltage รท Resistance = 12 รท 12 = 1 A.
Question 6: 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?
- 160 lbs (Correct answer)
- 200 lbs
- 250 lbs
- 40 lbs
Correct answer: 160 lbs
Ideal output = 40 ร 5 = 200 lbs; actual output = 200 ร 0.80 = 160 lbs due to 80% efficiency.
Question 7: Which property of a material describes its ability to return to its original shape after a deforming force is removed?
- Plasticity
- Ductility
- Elasticity (Correct answer)
- Brittleness
Correct answer: Elasticity
Elasticity is the property that allows a material to recover its original shape after stress is removed.
FCTC FREE FCTC Test Mechanical Reasoning Principles Questions and Answers 5
A 200-lb barrel is rolled up a 15-foot ramp to a platform 5 feet high.
Ignoring friction, what is the force required?