Here, we present a series of sample use cases that highlight some of the scientific objectives that could be enabled by phase 1 of the SKA (SKA1). This set consists of examples that include a broad range of scientific applications requiring the frequency coverage of SKA1-LOW and SKA1-MID ([AD3]), as well as the extended high frequency coverage that could be enabled by the advanced instrumentation programme band 6 receivers (beyond 15 GHz; [RD6]). These are intended to serve as examples, and should not be regarded as a substitute for the system level 1 requirements document. […]