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Half-line
Half-line may refer to: *Half-line (geometry) In geometry, a straight line, usually abbreviated line, is an infinitely long object with no width, depth, or curvature, an idealization of such physical objects as a straightedge, a taut string, or a ray of light. Lines are spaces of dimens ..., half of a line * The half-way line divides the (soccer) football pitch in two halves * Alliterative verse#Metrical form, half of a line of poetry {{disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Half-line (geometry)
In geometry, a straight line, usually abbreviated line, is an infinitely long object with no width, depth, or curvature, an idealization of such physical objects as a straightedge, a taut string, or a ray of light. Lines are spaces of dimension one, which may be embedded in spaces of dimension two, three, or higher. The word ''line'' may also refer, in everyday life, to a line segment, which is a part of a line delimited by two points (its ''endpoints''). Euclid's ''Elements'' defines a straight line as a "breadthless length" that "lies evenly with respect to the points on itself", and introduced several postulates as basic unprovable properties on which the rest of geometry was established. ''Euclidean line'' and ''Euclidean geometry'' are terms introduced to avoid confusion with generalizations introduced since the end of the 19th century, such as non-Euclidean, projective, and affine geometry. Properties In the Greek deductive geometry of Euclid's ''Elements'', a g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Football Pitch
A football pitch or soccer field is the playing surface for the game of association football. Its dimensions and markings are defined by Law 1 of the Laws of the Game (association football), Laws of the Game, "The Field of Play". The pitch is typically made of natural Sod, turf or artificial turf, although amateur and recreational teams often play on dirt fields. Artificial surfaces are allowed only to be green in colour. All line markings on the Pitch (sports), pitch form part of the area which they define. For example, a ball on or above the touchline is still on the field of play, and a foul committed over the line bounding the penalty area results in a penalty. Therefore, a ball has to completely cross the touchline to be out of play, and a ball has to fully cross the goal line (between the goal posts) in order for a goal to be scored; if any part of the ball is still on or above the line, a goal is not scored and the ball is still in play. The field descriptions that apply ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
