Questions and Answers Flashcards
6 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 6 Questions and Answers flashcards as text
What is the difference between potential energy and kinetic energy?
Answer: Potential energy is stored energy; kinetic energy is energy of motion
Potential energy is stored energy due to an object's position or configuration (gravitational PE, elastic PE, chemical PE). Kinetic energy is the energy an object possesses due to its motion (KE = ½mv²).
Why does a spinning gyroscope resist changes to its orientation?
Answer: Conservation of angular momentum
A spinning gyroscope resists changes to its axis of rotation due to conservation of angular momentum. A torque applied to the gyroscope causes it to precess (slowly rotate around a different axis) rather than simply tipping over.
What is the function of a counterweight in a crane?
Answer: To balance the load and prevent the crane from tipping over
A counterweight on the opposite side of the crane from the load creates a balancing moment (torque) that prevents the crane from tipping. Its weight and position are calculated to ensure stability under various load conditions.
What is the advantage of using a worm-and-wheel gear system in a lifting device?
Answer: It is self-locking, preventing the load from dropping when the input stops
Worm-and-wheel gear systems are self-locking — the wheel cannot drive the worm due to the thread angle and friction. This means a load stays in position without needing a brake when the operator stops turning the worm.
What effect does increasing the length of a pendulum have on its period?
Answer: Period increases
The period of a simple pendulum increases with length: T = 2π√(L/g). A longer pendulum swings more slowly (longer period) because it must travel a greater arc distance for each oscillation.
What is the center of gravity of an object?
Answer: The point where all the weight can be considered to act
The center of gravity is the point at which the entire weight of an object can be considered to be concentrated. For a uniform object, it coincides with the geometric center; for irregular objects, it depends on mass distribution and may even lie outside the object.