How can you add a dimension to a sketch in SolidWorks?

Adding a dimension to a sketch in SolidWorks is most efficiently accomplished using the Smart Dimension tool from the Sketch tab. This tool is specifically designed for the purpose of applying dimensions to entities in a 2D sketch, allowing for precise control over the size, position, and relationships between sketch entities.

When you select the Smart Dimension tool, you can easily click on two points or edges to create a dimension that reflects the linear distance between them, or click on a circle or arc to specify its radius or diameter. This intuitive process streamlines the dimensioning workflow and ensures that dimensions are applied in a way that is conducive to the design intent.

Other methods mentioned, such as the Dimension tool from the Features tab, are not applicable for sketching. The Features tab focuses on 3D features and operations, making it irrelevant for sketch dimensioning tasks. Applying dimensions under the Property Manager is more about modifying existing entities rather than adding new dimensions directly. The option to insert dimensions from the Insert menu does exist but is less common and practical in the context of sketching, since Smart Dimension more effectively manages the sketch dimensioning process.