Glossary
wedge
A wedge is two inclined planes set back to back, driven into a material to split it or hold it apart. The thinner it is, the less force it takes to drive in.
A wedge is two inclined planes set back to back, and it works by being driven into something to split it or hold it apart. An axe, a knife, a chisel, a nail, a splitting maul and the blades of a pair of scissors are all wedges.
Its mechanical advantage comes from thinness: the slimmer a wedge is in proportion to its length, the less force it takes to drive in, though you must drive it deeper to do the same work. The effort moves the wedge along its length while the cut opens only by its width — the distance-for-force trade once more.
Wedges cut, split, tighten and hold. A knife and an axe are cutting wedges, while a nail, a doorstop and a shim are holding ones. Friction is what makes them work: it is the reason a driven wedge does not back out again.
Taught in
Related terms
- inclined plane — An inclined plane is a sloping surface used to raise a load gradually instead of lifting it straight up. A gentle long ramp needs less force than a steep, short one.
Source: Official ASVAB — subtest descriptions (what each subtest asks) and the CAT-ASVAB scored-question counts (accessed 2026-09)