Which of the following best describes thermal contraction?

Thermal contraction refers to the phenomenon where materials, including metals, decrease in size or volume as their temperature drops. When temperatures lower, the energy of the atoms within the material decreases, causing them to move closer together. This results in a reduction in the overall dimensions of the material. The description accurately captures the essence of thermal contraction, which is critical in manufacturing and construction, where temperature variations can significantly impact material performance and integrity.

Understanding thermal contraction is crucial for sheet metal workers, as it affects the fitting and assembly of components in various applications. Proper consideration of thermal contraction during design and fabrication helps prevent issues such as gaps and misalignment in finished products.