A Mobius Strip is an amusing three-dimensional object whose surface has only one side. Huh? Well, most objects you can imagine have a surface with two sides. For example, an ordinary piece of paper ... Continue reading
Originally, each country had its own, and rather poorly reproducible, unit of luminous intensity; it was necessary to wait until 1909 to see a beginning of unification on the international level, when ... Continue reading
The origins of the meter go back to at least the 18th century. At that time, there were two competing approaches to the definition of a standard unit of length. Some suggested defining the meter as ... Continue reading
A prime number is a number that is divisible only by one and by itself. Factors are numbers that can be divided into a number with no remainder. The factors of 18 are the numbers 1, 2, 3, 6, 9, and ... Continue reading
