Name a common low explosive used in demolition.

Black powder, also known as gunpowder, is a common low explosive used in demolition. Its composition of saltpeter (potassium nitrate), charcoal, and sulfur allows it to burn rapidly and produce a significant volume of gas, which is useful for applications in demolition. This characteristic makes black powder effective for creating enough pressure to break apart materials such as concrete and rock.

While other options listed are also explosive materials, they serve different purposes or are classified differently. For example, detonating cord is a type of linear explosive that is used primarily to initiate other explosives rather than for direct demolition. Ammonium nitrate is primarily used in bulk explosives and is often combined with fuels to create ANFO (Ammonium Nitrate Fuel Oil), while nitroglycerin is classified as a high explosive and is used in applications requiring a much greater velocity of detonation. These distinctions underscore why black powder is specifically recognized as a common low explosive suitable for demolition tasks.