A concave mirror whose cross-section is shaped like the tip of a parabola. Most of the light, radio waves, sound, and other radiation that enter the mirror straight on is reflected by the surface and converges on the focus of the parabola, where being concentrated, it can be easily detected. Conversely, radiation emanating from the focal point reflects from the inner surface of the mirror into a fairly direct beam of nearly parallel radiation that can be aimed at a target. Parabolic mirrors are the basis of parabolic antennae and automobile headlights, as well as some megaphones and telescopic mirrors.
The Dictionary Is Political: The Complication With CollusionAsk anyone what the political byword of our moment is and they will likely say collusion.
What Are 5 Types Of Lexical Verbs?Lexical verbs are the main verbs (or action words) in a sentence. They can show the subject’s action or express a state of being. They fall into several categories: transitive, intransitive, linking, dynamic, and static. Transitive and Intransitive Verbs A transitive verb expresses action, and needs a direct object to receive that action. “Alice sees the candle,” is an example. Sees is the lexical verb …
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