Mechanical Aptitude Forces and Motion Principles Questions and Answers 3

Question 1

What type of friction acts on an object that is sliding across a surface?

Accepted Answer

Kinetic friction

Answer

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.

Question 2

What force keeps an object moving in a circular path?

Accepted Answer

Centripetal force

Answer

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.

Question 3

If you double the distance between two gravitating objects, what happens to the gravitational force between them?

Accepted Answer

It becomes one-quarter

Answer

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.

Question 4

What is the mechanical advantage of a lever where the effort arm is 3 meters and the load arm is 1 meter?

Accepted Answer

3

Answer

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.

Question 5

A 2 kg ball rolling at 5 m/s has what momentum?

Accepted Answer

10 kg·m/s

Answer

Momentum equals mass times velocity: p = mv = 2 kg × 5 m/s = 10 kg·m/s.

Mechanical Aptitude Test Practice Test

Mechanical Aptitude Test Practice Test

Mechanical Aptitude Forces and Motion Principles Questions and Answers 3