Physical quantities and physical dimensions are among the first concepts
encountered by students in their undergraduate career. In this pedagogical
review, I will start from these concepts and, using the powerful tool of
dimensional analysis, I will embark in a journey through various branches of
physics, from basic mechanics to quantum gravity. I will also discuss a little
bit about the fundamental constants of Nature, the so-called "cube of Physics",
and the natural system of units.Comment: 20 pages, 6 figures; v2: minor changes, reference added. Pedagogical
article in Portuguese addressed to undergraduate student
