PIPEPREP AI
13 questions · 13 min

Mechanical Comprehension: The GAN Aptitude Test Section, Explained

Mechanical Comprehension is 13 illustrated questions in 13 minutes, in the Bennett style: two gears, a block and tackle, a lever, a hydraulic jack, and a question about which way something turns or how much force it takes. No formulas are required and no calculator is allowed — it tests physical intuition.

Questions
13
Time
13 min
Calculator
Not allowed

That is a full minute per question. This section is one of six on the battery, which runs about 140 questions in roughly two hours — see the full GAN aptitude test breakdown for how the whole thing fits together.

What this section measures

Whether you already think like someone who works with machines. A pipe trades apprentice rigs loads, cracks stubborn fittings, and works around pumps and valves from the first week.

It is the one section where the answers are genuinely derivable from a handful of principles rather than memorised, so a focused week of review moves it a long way.

How to train it

One principle carries most of the section

Every simple machine trades force for distance. You never get both. If a setup lets you pull with less force, you will pull further; if it moves the load faster, you will push harder. When an answer choice offers less force AND less distance, it is almost always the trap.

Levers and torque: force times distance from the pivot

A longer handle multiplies force. A balance tips toward whichever side has the larger weight-times-distance product. Moving a load closer to the fulcrum makes it easier to lift but moves it less per stroke. Most lever items are one multiplication.

Pulleys: count the ropes supporting the moving block

Mechanical advantage equals the number of rope segments actually supporting the load block. A fixed pulley supports none — it only redirects, so it gives you nothing but a better pulling angle. Each supporting segment divides the force and multiplies the rope you must pull.

Gears: smaller turns faster, meshing reverses

In a meshed pair the smaller gear turns faster and with less torque. Directly meshed gears turn opposite ways; an idler between them restores the original direction; a chain or belt drive keeps both the same way. Speed scales by the tooth ratio.

Hydraulics: pressure is equal, force follows area

Pressure is the same throughout a confined fluid, so a bigger ram pushes harder — force equals pressure times area. The distance trade applies here too: a jack that multiplies force twenty-fold moves the load a twentieth as far.

Where applicants lose points

  • Assuming a fixed pulley halves the force. It does not — it only changes direction.
  • Adding the stages of a compound machine instead of multiplying them. Bolt cutters with 5:1 handles and a 4:1 jaw linkage give 20:1, not 9:1.
  • Answers offering both more force and more speed. No machine gives you both; that option exists to catch you.

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Frequently asked

What is on the mechanical comprehension section?

Thirteen illustrated questions covering levers and torque, pulleys and block-and-tackle, gears and belt drives, hydraulics, springs, and centre of gravity. They test intuition about how machines behave, not memorised formulas.

Do I need physics knowledge to pass it?

No formal physics is required. Understanding that every simple machine trades force for distance, plus the basics of levers, pulleys, gears and hydraulics, covers the large majority of items.

Is it the same as the Bennett Mechanical Comprehension Test?

It is the same style — illustrated, intuition-based mechanical questions. Confirm the exact instrument with your local, since the assessments used vary between locals and providers.

The other five sections

Ready to sit the whole thing? Take a free full-length practice test in the GAN format — timed sections, no calculator, instant scoring.

Drill Mechanical until it is your best section

Reading about a section and scoring on it are different things. The app has ten full-length timed batteries plus dedicated mechanical drills, so test day is your eleventh run at it, not your first.

Download on the App Store

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