A charge refers to an electrical property of matter that causes it to experience a force when placed in an electromagnetic field. A negative charge means an excess of electrons, while a positive charge means a deficiency of electrons.
A charge is measured in coulombs (C), which is the unit of electric charge in the International System of Units (SI). One coulomb is equivalent to the charge of 6.241 x 10^18 electrons or protons.
The main difference between a positive and negative charge is the direction of the electric field lines. For a positive charge, the electric field lines radiate outwards, while for a negative charge, the electric field lines converge inwards.
Like charges repel each other, while opposite charges attract each other. This is due to the fundamental force of electromagnetism, which causes charged particles to exert a force on each other.
The behavior of matter is significantly influenced by the presence of charges. Charges can cause objects to attract or repel each other, and they also play a crucial role in chemical reactions and the functioning of electronic devices.