Mechanical Aptitude Test Mechanical Aptitude Forces and Motion Principles 1

Question 1

A 5 kg cart is pulled by a rope exerting 30 N of force. Friction opposes the motion with 5 N. What is the acceleration of the cart?

Accepted Answer

5 m/s²

Answer

Net force = 30 N − 5 N = 25 N. Using Newton's second law, a = F/m = 25 N ÷ 5 kg = 5 m/s².

Question 2

A 1,200 kg car decelerates from 20 m/s to a complete stop in 4 seconds. What average braking force was applied?

Accepted Answer

6,000 N

Answer

Deceleration = Δv / t = 20 / 4 = 5 m/s². Braking force = m × a = 1,200 × 5 = 6,000 N.

Question 3

A 2 kg ball is dropped from rest and falls freely for 3 seconds (g = 10 m/s²). What is its velocity just before it hits the ground?

Accepted Answer

30 m/s

Answer

Using v = u + at with u = 0, v = 0 + (10)(3) = 30 m/s. Gravity accelerates the ball by 10 m/s every second.

Question 4

Three forces act on a single object: 40 N east, 40 N west, and 20 N north. What is the net resultant force?

Accepted Answer

20 N north

Answer

The 40 N east and 40 N west forces cancel each other out, leaving only the 20 N northward force as the net resultant.

Question 5

A stationary 8 kg block has a constant 24 N force applied to it. How far does it travel in 3 seconds?

Accepted Answer

13.5 m

Answer

Acceleration a = F/m = 24/8 = 3 m/s². Distance d = ½at² = ½ × 3 × 9 = 13.5 m.

Mechanical Aptitude Test Practice Test