Mechanical Deductive Reasoning Test

Reasoning about relative properties of physical systems such as the direction of motion, relative speed, and relative mass is a powerful strategy to assess one’s ability to create mental simulations in order to evaluate physical events.

This kind of test taps into a person’s ability to access their mental models, learned rules or cached results to generate solutions to a problem1.


In the following test, you will be shown images portraying objects that can mechanically interact with each other. All the questions will relate to how these objects would react in real life.


Scale - On a perfectly balanced scale, you have one plate with two weights, one with 10 Kg and the other with 5 Kg. If the plates are balanced, how many Kg are in the second plate? The answer is 15 Kg, otherwise, the plates would tilt.

Gears - If you have only two gears connected (without any belt pulley system) and you know that one gear turns counterclockwise, in which direction does the other gear rotate? The answer is clockwise, as connected gears rotate in opposite directions.


This test is designed as an entertaining and educational tool. The results do not constitute a psychological or psychiatric evaluation of any kind and may not offer an accurate portrait of the mental fitness of the test taker. We do not guarantee the accuracy of the results and these should not be used as an indicator of the capacities of the individual for a specific purpose.
Responses may be recorded and used for research purposes or to be otherwise distributed. All responses are recorded anonymously. 


1 Markman, A & Gentner, D. (2001). Thinking. Annual Review of Psychology, 52, 223-247.