Report Abuse. Calcium can exist in solid, liquid, or gas form, depending on the temperature. And anything which does not occur naturally is synthetic. The word has nothing to do with elemental properties, as far as I know.twitching_green_grasshopper Â· 7 years ago.olid, liquid and gas are states or phases of an element or substance. But most substances can exist in all three states depending on temperature and pressure.
The basic premise of the telescope tube is to align two lenses the appropriate distance from each other. For this telescope, the lenses are a concave convex (one side curved out and the other curved in) and a plano concave (one flat side and one side curved in). The plano concave lens is used as the eyepiece with the plano (flat) side facing the eye.
For a spherically curved mirror in air, the magnitude of the focal length is equal to the radius of curvature of the mirror divided by two. The focal length is positive for a concave mirror, and negative for a convex mirror.In the sign convention used in optical design, a concave mirror has negative radius of curvature, so.he focal length of a lens determines the magnification at which it images distant objects. It is equal to the distance between the image plane and a pinhole that images distant objects the same size as the lens in question.