Mechanical Aptitude Test

A mechanical aptitude test shows you a drawing of a simple machine (gears, a lever, a rope over pulleys, two wheels on a belt) and asks what it will do or how much force it needs. Most questions come down to a handful of principles, and each one can be applied in seconds once you have practised it. This guide covers the tests employers use, the seven principles with a worked example each, and how to spend your time. When you are ready, take the free mechanical aptitude practice test: 20 diagram questions in 15 minutes, scored, with a review of every mistake.

Which tests you might meet

• Bennett Mechanical Comprehension Test (BMCT), published by Pearson (TalentLens). Illustrated questions about everyday physical situations; the current edition is commonly described as 55 items in 25 minutes.
• Ramsay Corporation tests such as the Mechanical Aptitude Test (MAT) and MechTest, common in manufacturing, utilities and maintenance hiring.
• Wiesen Test of Mechanical Aptitude (WTMA), designed with a low reading load so that vocabulary does not drive the score.
• ASVAB Mechanical Comprehension, a subtest of the US military's aptitude battery that feeds into the scores for mechanical and maintenance jobs.
• SHL, Aon and other publishers include a mechanical comprehension section in technical and apprentice batteries.

The formats differ in length and time limit, but the content overlaps heavily. If you can do the seven things below quickly, you can answer most of what any of them asks.

1. Gears: direction is a parity count

Two meshing gears turn in opposite directions. In a chain, the direction flips at every mesh, so gears 1, 3, 5 turn one way and gears 2, 4, 6 the other.

Example. Five gears in a row; gear A turns clockwise. Which way does gear E turn? E is the fifth gear, an odd position, so it turns the same way as A: clockwise. You never need to trace the gears in between.

Two traps: gears fixed on the same shaft turn the same way at the same speed (no flip), and a closed ring of gears with an odd number of gears cannot turn at all. A ring of three gears jams, because each gear would have to turn both ways at once; a ring of four turns freely.

2. Gears: speed follows the teeth

The teeth passing the meshing point per second are the same for both gears, so a gear with fewer teeth must turn faster:

driven rpm = driver rpm × driver teeth ÷ driven teeth

Example. Gear A has 20 teeth and turns at 90 rpm. It drives gear B with 30 teeth. B turns at 90 × 20 ÷ 30 = 60 rpm, in the opposite direction.

An idler gear between them changes nothing about the speed of the last gear (its teeth cancel out), only the direction. With gears on a shared shaft, multiply the ratios: A (20 teeth) drives B (40); C (15) sits on B's shaft and drives D (30). At 120 rpm for A: B turns at 120 × 20 ÷ 40 = 60 rpm, so does C, and D turns at 60 × 15 ÷ 30 = 30 rpm.

3. Levers: moments balance

A beam balances when the turning effect (the moment, force × distance from the pivot) is equal on both sides.

Example. On a seesaw, 6 kg sits 2 m left of the pivot and 3 kg sits 5 m to the right. Left moment: 6 × 2 = 12. Right moment: 3 × 5 = 15. The right side is larger, so the right side goes down, even though the heavier weight is on the left. Test writers like exactly this set-up: the heavier weight close in, the lighter one far out.

Force to balance. A 600 N load sits 2 m from the pivot. What downward force 3 m from the pivot on the other side balances it? F × 3 = 600 × 2, so F = 400 N.

The same rule covers every lever class. With a bar hinged at one end, a load 2 m from the hinge and your hand 5 m out (a wheelbarrow), F × 5 = load × 2: you lift less than the load. With your hand 1 m out and the load 4 m out (tweezers, your forearm), F × 1 = load × 4: you need four times the load, and you gain speed and reach in exchange.

4. Pulleys: count the supporting ropes

In a pulley system, the load is shared by the rope segments that hold up the moving block. With n of them, ignoring friction and the weight of the pulleys:

force = load ÷ n

Example. A 240 N load hangs from a moving block held by four rope segments. The pull needed is 240 ÷ 4 = 60 N. A single fixed pulley (n = 1) needs the full 240 N; it only changes the direction of the pull.

The price is distance. Work in equals work out, so with four supporting segments you pull 4 m of rope to lift the load 1 m. If a question asks how much rope you pull to raise a load 2 m with three supporting segments, the answer is 6 m. Count only segments attached to or wrapped around the moving block; the end you pull on counts only if it pulls upward from the block itself.

5. Belts and wheels: open keeps, crossed reverses

Wheels joined by an open belt turn the same way; a crossed belt (the figure of eight) makes them turn opposite ways. Speeds follow the diameters, just as gear speeds follow teeth:

driven rpm = driver rpm × driver diameter ÷ driven diameter

Example. Wheel A, 50 cm across, turns clockwise at 60 rpm and drives wheel B, 20 cm across, with a crossed belt. B turns counter-clockwise at 60 × 50 ÷ 20 = 150 rpm. In a chain of three wheels, count the crossed belts: an even number means the last wheel turns like the first.

6. Springs and ramps: share the load, spread the effort

Springs in series (one hanging below the other) each carry the whole load, so their stretches add. Springs in parallel (side by side, joined at the bottom) share the load, so each stretches less.

Example. Each spring stretches 4 cm under 10 N. Two in series carrying 30 N: each stretches 12 cm, total 24 cm. Two in parallel carrying 30 N: each carries 15 N and stretches 6 cm.

Inclined planes trade force for distance like pulleys do. Without friction, the push needed along the ramp is:

force = weight × height ÷ length

Example. A 600 N box pushed up a ramp 6 m long and 2 m high needs 600 × 2 ÷ 6 = 200 N. Of two ramps to the same height, the longer one always needs less force. Of two ramps with different heights, compare height ÷ length, not the length alone.

7. Fluids: depth decides pressure

Pressure in a liquid depends only on the depth, not on the container's shape or how much liquid it holds. A narrow tube filled 50 cm deep has more pressure at the bottom than a wide tank filled 30 cm deep.

Hydraulic press. The pressure is the same on both pistons, so force scales with area. A 20 N push on a 4 cm² piston gives 20 × 40 ÷ 4 = 200 N on a 40 cm² piston. As with pulleys, the large piston moves less: a tenth of the distance.

Real tests sometimes add electricity basics (bulbs in series share the voltage and glow dimmer than bulbs in parallel), centre of gravity (a low, wide base is more stable) and heat (metals expand when heated). The habit is the same: name the principle, then apply it.

A timing plan

• Do direction and comparison questions by rule. Gear and belt direction are a count; "which side goes down" is two multiplications. These should take seconds, not minutes.
• Spend the saved time on two-step questions: shared shafts, pulley distance, spring systems, hydraulics.
• Eliminate the impossible. A pulley never needs more force than the load. A smaller wheel never turns slower than the bigger one driving it. A longer ramp to the same height never needs more force.
• Check the marking rule. If wrong answers cost nothing, never leave a blank.

Practise under the clock

Reading about principles helps; applying them with a timer running is what moves your score. The mechanical aptitude practice test generates a fresh set of 20 questions every run, gets harder as it goes, and shows your result per topic plus the rule behind every question you missed. For the spatial side that some technical batteries add, try mental rotation, and for the arithmetic that sits under force and speed questions, the numerical reasoning practice.

Check how ready you are

After a few practice runs, the mechanical aptitude readiness check puts your results for every section of the test in one report: your typical score (the one that matters with a single attempt on the day), the section to fix first, and a day-by-day plan up to your test date.

FAQ

What is a mechanical aptitude test? A timed multiple-choice test that shows drawings of simple machines (gears, levers, pulleys, belts, springs, ramps, fluids) and asks what they will do or how much force they need. Employers use it for engineering, manufacturing, maintenance, utilities and military roles.

Is a mechanical reasoning test the same thing? Yes, in practice. Mechanical aptitude, mechanical reasoning and mechanical comprehension are names for the same picture-and-question format; the Bennett test calls it comprehension, the ASVAB subtest too.

Which principle comes up most? Gears and levers. Gear direction is a parity count (every mesh reverses the direction) and lever questions compare force × distance on each side of the pivot.

How do I count pulley ropes? Count the rope segments that hold up the moving block. The force needed is the load divided by that number, and you pull that many metres of rope for each metre the load rises.

Can I practise for free? Yes. The GamePrep mechanical aptitude practice test gives 20 diagram questions in 15 minutes, a percentile and a review of every mistake, with a new set each run.

GamePrep is independent and not affiliated with Pearson, TalentLens, Ramsay Corporation, Wiesen, SHL, Aon, the US Department of Defense or any test publisher. The examples here are written for practice and are not taken from any real test.