"उपकरण": अवतरणों में अंतर

such as the [[knifeचाकु]], [[scythe]] or [[sickle]], are wedge-shaped implements that produce a [[Shear stress|shearing force]] along a narrow face. Ideally, the edge of the tool needs to be [[Hardness|harder]] than the material being cut or else the blade will become dulled with repeated use. But even resilient tools will require periodic [[sharpening]], which is the process of removing deformation wear from the edge. Also [[gouge]]s and [[drill bit]]s.