Mechanical Aptitude Forces and Motion Principles Questions and Answers

Question 1

An object is moving at a constant velocity of 15 m/s. According to Newton's First Law of Motion, which of the following must be true?

Accepted Answer

The net force acting on the object is zero.

Answer

The object will eventually slow down due to inertia.

Answer

A constant force is required to maintain its velocity.

Answer

The object's acceleration is 15 m/s².

Question 2

A mechanic uses a long wrench to loosen a tight bolt. Why is it more effective to apply force at the end of the wrench's handle rather than closer to the bolt?

Accepted Answer

It increases the torque applied to the bolt.

Answer

It increases the force applied to the bolt.

Answer

It reduces the friction between the bolt and the wrench.

Answer

It decreases the wrench's moment of inertia.

Question 3

If a person is in an elevator that is accelerating upwards, their apparent weight will be:

Accepted Answer

Greater than their actual weight.

Answer

Less than their actual weight.

Answer

Equal to their actual weight.

Answer

Zero.

Question 4

Which of the following best describes the difference between centripetal force and centrifugal force?

Accepted Answer

Centripetal force is a real force pulling an object towards the center of rotation, while centrifugal force is an apparent outward force.

Answer

They are equal and opposite forces that cancel each other out.

Answer

Centrifugal force is the force that keeps an object moving in a circle.

Answer

Centripetal force only applies to objects in a vacuum, while centrifugal force applies everywhere.

Question 5

A 100 kg box is pushed across a floor with a constant force. If the force of friction opposing the motion is 50 Newtons, what is the net force required to accelerate the box at 2 m/s²?

Accepted Answer

250 N

Answer

150 N

Answer

200 N

Answer

50 N

Question 6

Two gears are in mesh. Gear A has 15 teeth and Gear B has 30 teeth. If Gear A rotates clockwise, what will happen to Gear B?

Accepted Answer

It will rotate counter-clockwise at half the speed.

Answer

It will rotate clockwise at twice the speed.

Answer

It will rotate clockwise at half the speed.

Answer

It will rotate counter-clockwise at twice the speed.