cyclic motion
121Dark energy — Not to be confused with dark matter, dark fluid, or dark flow. Physical cosmology …
122hydrocarbon — hydrocarbonaceous, adj. /huy dreuh kahr beuhn, huy dreuh kahr /, n. any of a class of compounds containing only hydrogen and carbon, as an alkane, methane, CH4, an alkene, ethylene, C2H4, an alkyne, acetylene, C2H2, or an aromatic compound,… …
123endocrine system, human — ▪ anatomy Introduction group of ductless glands (gland) that regulate body processes by secreting chemical substances called hormones (hormone). Hormones act on nearby tissues or are carried in the bloodstream to act on specific target organs… …
124Cycles of Time (book) — Cycles of Time: An Extraordinary New View of the Universe   …
125Oscillation — For other uses, see oscillator (disambiguation) and oscillation (mathematics). An undamped spring–mass system is an oscillatory system. Oscillation is the repetitive variation, typically in time, of some measure about a central value (often a… …
126Sling (weapon) — A sling is a projectile weapon typically used to throw a blunt projectile such as a stone. It is also known as the shepherd s sling.A sling has a small cradle or pouch in the middle of two lengths of cord. The sling stone is placed in the pouch.… …
127Rotation — This article is about movement of a physical body. For other uses, see Rotation (disambiguation). A polyhedron resembling a sphere rotating around an axis. A rotation is a circular movement of an object around a center (or point) of rotation. A… …
128Action (physics) — In physics, the action is a particular quantity in a physical system that can be used to describe its operation. Action is an alternative to differential equations. The action is not necessarily the same for different types of systems.The action… …
