TalentLens Mechanical Comprehension 5 — Questions and Answers
Question 1: A pneumatic cylinder uses compressed air at 100 PSI acting on a 3-square-inch piston. What force does it exert?
- 33 lbs
- 100 lbs
- 300 lbs (Correct answer)
- 900 lbs
Correct answer: 300 lbs
Force = Pressure × Area = 100 PSI × 3 in² = 300 lbs.
Question 2: A double-block-and-tackle system has two pulleys on a fixed block and two on a moving block. What is its ideal mechanical advantage?
- 2
- 3
- 4 (Correct answer)
- 8
Correct answer: 4
A block-and-tackle with 4 rope segments supporting the load has an IMA of 4.
Question 3: A shaft transmits power through a belt drive. If the belt slips, what is the most likely effect on the driven pulley?
- The driven pulley speeds up
- The driven pulley slows down or stops (Correct answer)
- Power transmission doubles
- Torque on the driven pulley increases
Correct answer: The driven pulley slows down or stops
Belt slip reduces friction force, so less torque and speed are transferred to the driven pulley.
Question 4: A structural column is most resistant to buckling when it is:
- Longer and slender
- Shorter and stockier (Correct answer)
- Made of the lightest material
- Fixed at only one end
Correct answer: Shorter and stockier
Shorter, stockier columns have a smaller slenderness ratio and are far more resistant to buckling under compressive loads.
Question 5: Heat is transferred from a hot stove burner to a pan sitting on it primarily by:
- Convection
- Radiation
- Conduction (Correct answer)
- Evaporation
Correct answer: Conduction
Direct contact between the burner and the pan transfers heat primarily through conduction.
Question 6: A wedge is driven under a heavy object to lift it. Which wedge requires less driving force for the same lift?
- A short, steep wedge
- A long, gradual wedge (Correct answer)
- A wider wedge
- A heavier wedge
Correct answer: A long, gradual wedge
A long gradual wedge has a greater mechanical advantage (longer slope for the same rise), requiring less driving force.
Question 7: An object is placed on a rotating platform. As the platform spins faster, which direction does the object tend to move?
- Toward the center
- Away from the center (outward) (Correct answer)
- In the direction of rotation
- Opposite the direction of rotation
Correct answer: Away from the center (outward)
Due to inertia, the object tends to move outward (centrifugal tendency) as rotational speed increases.
TalentLens Mechanical Comprehension 5
A pneumatic cylinder uses compressed air at 100 PSI acting on a 3-square-inch piston.
What force does it exert?