What is a coulomb?

A coulomb is defined as the amount of electrical charge that is carried by a current of one ampere flowing for one second. This definition leads to the understanding that a single coulomb is equivalent to approximately (6.25 \times 10^{18}) electrons. This fundamental relationship highlights the scale of electric charge in practical terms, bridging the macroscopic world of electric current and the microscopic world of atomic charge carriers.

In electrical calculations and applications, recognizing that one coulomb corresponds to this extensive number of electrons is crucial for understanding how large currents and electric charges can be analyzed. It embodies the principle of charge quantization, emphasizing that electric charge occurs in discrete packets, with the electron being the basic unit.

By grasping this concept, students can better comprehend the interactions between electric currents and their effects on circuits and devices, reinforcing their foundational knowledge in electricity and electronics.