The goal of descriptive investigation is to describe. It should provide factual, accurate and systematic descriptions of phenomena without attempting to infer causal relationships. It does not answer questions about the how, when, or why a particular phenomenon occurred.
A descriptive investigation includes a question but no hypothesis. Observations are recorded, but no comparisons are made and no variables are manipulated.
The electrons have negative charge, which means that the negative terminal of the battery will suply the electrons, thus they are present in excess on the negative cable and will jump from it to the positive cable. This current direction is called real current.