Specific gravity in a battery is influenced by which two factors?

The correct answer highlights that specific gravity in a battery is primarily influenced by the state of charge and temperature.

When a battery is charged, the concentration of the electrolyte (usually sulfuric acid in lead-acid batteries) increases, leading to a higher specific gravity. Conversely, as the battery discharges, the concentration decreases, resulting in a lower specific gravity. Therefore, the state of charge is directly correlated with the specific gravity readings.

Temperature also plays a crucial role in these measurements. Higher temperatures can decrease the viscosity of the electrolyte, which in turn can lead to variations in the specific gravity reading, even if the state of charge remains constant. This means that for accurate specific gravity readings, both the battery's state of charge and the ambient temperature must be considered, as they significantly affect the electrolyte's characteristics and density.

Other options, such as elevation or types of water, do not have a direct and significant effect on specific gravity, and while battery size and voltage can impact battery performance, they are not part of what determines specific gravity in the same way that state of charge and temperature do.