ASNT Industrial Radiography Radiation Safety Practice Test

Which particles are defined as having a mass approximately 1840 times that of an electron?

1. Neutrons

2. Electrons

3. Protons

4. Positrons

The correct answer is: Protons

The correct answer is protons, as they have a mass that is roughly 1840 times greater than that of an electron. This mass ratio is significant in understanding atomic structure, where protons, along with neutrons, make up the nucleus of an atom, while electrons orbit around the nucleus. The mass of a proton is approximately 1.67 x 10^-27 kilograms, compared to the mass of an electron, which is about 9.11 x 10^-31 kilograms. This substantial difference in mass is critical in the concept of atomic stability, charge balance, and the overall behavior of elements in chemical reactions. Understanding the mass of protons is essential in fields like nuclear physics and chemistry, where the interactions and arrangements of particles determine the properties of different isotopes and the behavior of materials under various conditions.