Electric charge has a sign. That sign is part of the physical source and determines the direction rule for electric forces.
Example
Electric charge has a sign. That sign is part of the physical source and determines the direction rule for electric forces. Exact arithmetic here means exact results for the stated model inputs; measured inputs still carry uncertainty and significant-figure limits.
highlighted = computed this step
Charge has a sign
Electric charge comes with a sign. A positive charge and a negative charge are different source types, not just different colors in a picture.
q>zeroorq<zero
The value includes the unit
The left charge is positive 2 coulombs. The right charge is negative 3 coulombs. The sign belongs to the charge value.
qleft=+2Cqright=−3C
Signs decide force direction
A charge sign does not say how strong the force is by itself. It sets the direction rule: matching signs push apart, opposite signs pull together.
same signs repelopposite signs attract
The sign rule has only two outcomes
Scan the sign pairs before thinking about size. Matching signs repel; opposite signs attract. The diagram shows one positive and one negative source, while the table lists the rule.