Protonladdningsvärde

Protonladdningsvärde, often referred to as the elementary charge, is a fundamental physical constant that represents the magnitude of the electric charge of a single proton. It is also equal in magnitude but opposite in sign to the electric charge of a single electron. This value is quantized, meaning that any observable electric charge in nature is an integer multiple of this elementary charge.

The protonladdningsvärde is denoted by the symbol 'e'. Its accepted value in SI units is approximately 1.602176634 × 10⁻¹⁹ coulombs. This means that a single proton carries a positive charge of this magnitude, while an electron carries a negative charge of the same magnitude. The discovery and characterization of this fundamental charge were crucial steps in the development of atomic physics and quantum mechanics.

The concept of quantized charge was first experimentally demonstrated by Robert Millikan in his oil-drop experiment in the early 20th century. He showed that the charges on the oil droplets were always discrete multiples of a smallest unit of charge. This smallest unit is what we now understand as the protonladdningsvärde. This constant is a cornerstone of electromagnetism and is essential for understanding phenomena ranging from the behavior of atoms to the operation of electronic devices.