In the fraction 7/12, 7 is called the numerator and 12 is called the denominator. Following are some more fractions: (i) The fraction 5/7 is read as âfive-seventhâ which means that 5 parts out of 7 equal parts in which the whole is divided. In the fraction 5/7, 5 is called the numerator and 7 is called the denominator. (ii) The fraction 3/10 is read as âthree-tenthâ which means that 3 parts out of 10 equal parts in which the whole is divided. In the fraction 3/10, 3 is called the numerator and 10 is called the denominator.
The definition of opaque is not capable of having light pass through or hard to understand. 1  An example of opaque is the quality of a black sheet of paper. 2  An example of opaque is the study of astrophysics.
Obsidian, natural glass of volcanic origin that is formed by the rapid cooling of viscous lava. Obsidian is extremely rich in silica (about 65 to 80 percent), is low in water, and has a chemical composition similar to rhyolite. Obsidian has a glassy lustre and is slightly harder than window glass. Though obsidian is typically jet-black in colour, the presence of hematite (iron oxide) produces red and brown varieties, and the inclusion of tiny gas bubbles may create a golden sheen.