sähkönvaraus
Sähkönvaraus, often translated as electric charge, is a fundamental property of matter that causes it to experience a force when placed in an electromagnetic field. It is a scalar quantity, meaning it only has magnitude and no direction. There are two types of electric charge: positive and negative. Like charges repel each other, while opposite charges attract. The smallest unit of observable charge is the elementary charge, denoted by 'e', which is the magnitude of the charge of a single electron or proton. Protons carry a positive charge of +e, and electrons carry a negative charge of -e. Atoms are typically electrically neutral, meaning they have an equal number of protons and electrons. When an atom gains or loses electrons, it becomes an ion, acquiring a net positive or negative charge. Charge is conserved, meaning it cannot be created or destroyed, only transferred from one object to another. The SI unit for electric charge is the coulomb (C). One coulomb is defined as the charge transported by a constant current of one ampere in one second. The concept of electric charge is central to understanding electricity and magnetism, including phenomena like static electricity, electric currents, and magnetic fields.