Umbrella
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An umbrella is a folding canopy supported by wooden or metal ribs that is mounted on a wooden, metal, or plastic pole. It is usually designed to protect a person against sun or rain. Initially, they w
An umbrella
Woman holding a parapluie at Zenkō-ji, Nagano, Japan
Relief of an Egyptian umbrella. These were used as sunshade and fan alike (flabellum).
Bas-relief of the Persian king Xerxes I (485–465 BC) at Persepolis
Umbra, penumbra and antumbra
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The umbra, penumbra and antumbra are three distinct parts of a shadow, created by any light source after impinging on an opaque object of lesser size. In cases of equal or larger impinging objects, on
Umbrella
…semi-fixed devices, used with patio tables or other outdoor furniture, or as points of shade on a sunny beach. The word umbrella evolved from the Latin umbra, meaning 'shadow' or 'shade from light' as it provided a shade from the sun. The Oxford English Dictionary records the first recorded usage in this…
Umbra, penumbra and antumbra formed through windows and shutters
Earth's umbra, as seen during a partial lunar eclipse