MECHANICAL APTITUDE Study Guide 2026

For a simply supported beam with a central point load, the bending moment diagram forms a triangle with its peak value at the midpoint load location.

The gear ratio is the number of teeth on the driving gear divided by the number on the driven gear: 60/20 = 3:1. The driven gear rotates 3 times for every 1 rotation of the driving gear, providing speed increase but torque reduction.

Ferrous metals contain iron as their primary component (steel, cast iron, wrought iron), while non-ferrous metals do not contain significant iron (aluminum, copper, brass, titanium). Ferrous metals are typically magnetic and susceptible to rust.

Viscosity is defined as the measure of a fluid's internal friction or its resistance to flow. A fluid with high viscosity, like honey, flows slowly because of the strong internal friction between its layers. A fluid with low viscosity, like water, flows easily.

A telescoping gauge expands to contact the inner walls of a bore, then is locked and measured with a micrometer for precise readings.

A worm gear provides high gear reduction in a compact space and is typically self-locking — the worm can drive the gear, but the gear cannot drive the worm. This makes worm gears ideal for applications requiring high torque and a built-in braking effect.