A goal of archery, featuring concentric spaced circles.
Concentric objects share the same center, axis or origin. The circles, tubes, cylindrical axes, discs and spheres can be concentric with each other. Note that two objects can have equal radii and be concentric and different. For example, two different meridians of a terrestrial globe are concentric and congruent, their common center is a point that represents the center of the Earth.
One of the best known examples of concentric circles is the spaced circles used in archery or firearms, and consequently any concentric design can be called an "objective" or a "target" (in the center). Examples of concentric phenomena
A concentric cable is a type of cable used in TN-C-S grounding systems, where the neutral combined core and earth completely surround the live core. This minimizes the risk of completely cutting through the combined neutral and the earth without first cutting through the live cores completely.
The contractions of the concentric muscles are those in which the muscle shortens.
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