EREnlistReadyASVAB & Army CareersOpen web app

ASVAB subject guide

Mechanical comprehension

Reason about force, motion, machines, fluids, and mechanical advantage.

Practice this subject in the appTake the 25-question test →

Core review

What to study

  • Longer lever arms can produce more torque for the same force.
  • Gears trade speed and direction for torque.
  • Pressure in a confined fluid is transmitted through the fluid.

Five-question review

Try original mechanical comprehension questions.

Attempt each question before opening the answer and explanation.

Question 1

For the same applied force, a longer lever arm produces:

  1. Less torque
  2. More torque
  3. Less mass
  4. More friction only
Reveal answer and explanation

Correct answer: More torque

Torque equals force times perpendicular lever-arm distance.

Question 2

When a small gear drives a larger gear, the larger gear generally turns:

  1. Faster with less torque
  2. Slower with more torque
  3. At the same speed
  4. Without changing direction
Reveal answer and explanation

Correct answer: Slower with more torque

The larger driven gear trades rotational speed for increased torque.

Question 3

An ideal single fixed pulley mainly changes the:

  1. Direction of force
  2. Mass of the load
  3. Amount of work required
  4. Weight of the rope
Reveal answer and explanation

Correct answer: Direction of force

A fixed pulley redirects the pull but provides no ideal mechanical advantage.

Question 4

Hydraulic systems operate because pressure applied to a confined fluid is:

  1. Destroyed immediately
  2. Transmitted through the fluid
  3. Converted only to heat
  4. Limited to the top surface
Reveal answer and explanation

Correct answer: Transmitted through the fluid

Pascal’s principle states that pressure changes transmit throughout a confined fluid.

Question 5

Which surface usually produces the greatest friction?

  1. Rough dry concrete
  2. Smooth ice
  3. Lubricated steel
  4. Air cushion
Reveal answer and explanation

Correct answer: Rough dry concrete

Rough dry surfaces generally resist sliding more than smooth or lubricated surfaces.

Related preparation

Continue across the ASVAB.

Subject guideArithmetic reasoningTurn a word problem into a few clear mathematical steps.Subject guideWord knowledgeUse vocabulary knowledge and context to find the closest meaning.Subject guideParagraph comprehensionFind the answer supported by the passage rather than outside knowledge.Subject guideMathematics knowledgeApply algebra, geometry, exponents, and number rules accurately.

Track your accuracy instead of guessing your weak areas.

The free web app records subject attempts locally on your device and highlights areas that deserve more study.

Open ASVAB practice