Forces and Motion Principles 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 Forces and Motion Principles Questions and Answers flashcards as text
What type of friction acts on an object that is sliding across a surface?
Answer: Kinetic friction
Kinetic (or sliding) friction acts on objects already in motion across a surface. It is typically less than static friction, which is why it takes more force to start an object moving than to keep it moving.
What force keeps an object moving in a circular path?
Answer: Centripetal force
Centripetal force is the net inward force that keeps an object moving along a curved path. It always points toward the center of the circular path. Examples include tension in a string swinging a ball and gravity keeping planets in orbit.
If you double the distance between two gravitating objects, what happens to the gravitational force between them?
Answer: It becomes one-quarter
Gravitational force follows an inverse-square law (F = Gm₁m₂/r²). Doubling the distance (r) means the force becomes 1/(2²) = 1/4 of the original force.
What is the mechanical advantage of a lever where the effort arm is 3 meters and the load arm is 1 meter?
Answer: 3
Mechanical advantage of a lever equals the effort arm length divided by the load arm length: MA = 3m / 1m = 3. This means you can lift a load three times heavier than the effort force applied.
A 2 kg ball rolling at 5 m/s has what momentum?
Answer: 10 kg·m/s
Momentum equals mass times velocity: p = mv = 2 kg × 5 m/s = 10 kg·m/s.
What is the acceleration due to gravity near Earth's surface?
Answer: 9.8 m/s²
The standard acceleration due to gravity near Earth's surface is approximately 9.8 m/s² (often rounded to 9.81 m/s² or simplified to 10 m/s² for quick calculations). This value varies slightly with altitude and latitude.