Physics (Year 12) - Electro-magnetism
There is an electrostatic force between 2 charged particles and is given by the following relationship which is also known as Coulomb’s law:
If the force is a positive value then this indicates that the two charged objects will repel; implying that either both have a positive charge or both have a negative charge. If the force is a negative value then this indicates that the two charged objects will attract; implying that one has a negative charge whilst the other has a positive charge. Hence it is important to include in your final answer if the force is attractive or repulsive.
Static electricity is exactly what it sounds like. It refers to electric charges which hare stationary (or static). It is usually observed on surfaces that have been rubbed together, which makes the surfaces charged.