Mechanical Aptitude Mechanical Aptitude Forces and Motion Principles Questions and Answers 2

Question 1

A 10 kg box is pushed across a floor with a force of 50 N while friction exerts 20 N in the opposite direction. What is the net acceleration of the box?

Accepted Answer

3 m/s²

Answer

Net force is 50 N - 20 N = 30 N, and acceleration = 30 N / 10 kg = 3 m/s².

Question 2

An object is moving at a constant velocity along a straight path. What can you conclude about the forces acting on it?

Accepted Answer

The net force is zero

Answer

Constant velocity means zero acceleration, which by Newton's first law means the net force is zero.

Question 3

A baseball pitcher throws a 0.15 kg ball at 40 m/s. If the throw takes 0.5 seconds, what average force did the pitcher apply?

Accepted Answer

12 N

Answer

Force = mass × change in velocity / time = 0.15 kg × 40 m/s / 0.5 s = 12 N.

Question 4

Two ropes are attached to a heavy crate. Rope A pulls north with 100 N and Rope B pulls east with 100 N. What is the approximate magnitude of the resultant force?

Accepted Answer

141 N

Answer

The resultant of two perpendicular 100 N forces is √(100² + 100²) ≈ 141 N.

Question 5

A 5 kg object falls freely from rest near Earth's surface. Ignoring air resistance, what is its speed after 3 seconds?

Accepted Answer

29.4 m/s

Answer

Speed = g × t = 9.8 m/s² × 3 s = 29.4 m/s.

Mechanical Aptitude Test Practice Test

Mechanical Aptitude Test Practice Test

Mechanical Aptitude Mechanical Aptitude Forces and Motion Principles Questions and Answers 2