A 2 metre carpenter's rule
Retractable flexible rule A ruler or rule is an instrument used in geometry, technical drawing and engineering/building to measure distances and/or to rule straight lines. Strictly speaking, the ruler is the instrument used to rule lines and the calibrated instrument used for determining measurement is called a measure. However, common usage is that a ruler is calibrated so that it can measure. Wikipedia does not have an article with this exact name. ...
Wikipedia does not have an article with this exact name. ...
Image File history File links CarpentersRule. ...
Image File history File links CarpentersRule. ...
Image File history File links TapeMeasure. ...
Image File history File links TapeMeasure. ...
Captain Nemo and Professor Aronnax contemplating measuring instruments in Twenty Thousand Leagues Under the Sea In physics and engineering, measurement is the activity of comparing physical quantities of realworld objects and events. ...
CalabiYau manifold Geometry (Greek Î³ÎµÏ‰Î¼ÎµÏ„ÏÎ¯Î±; geo = earth, metria = measure) is a part of mathematics concerned with questions of size, shape, and relative position of figures and with properties of space. ...
Technical drawing, also known as drafting, is the practice of creating accurate representations of objects for technical, architectural and engineering needs. ...
Several different designs of flexible instruments are used to determine length, such as the carpenter's rule, the ribbonlike tape measure used by tailors, and the retractable rule used especially in the construction trades and by home handyman, also known as a tape measure. As can be seen by the photos on this page, a 2 metre carpenter's rule can be folded down to a length of only 20 centimetres to easily fit in a pocket, and the 5 metre long tape easily retracts to fit within a smallsized housing. Selfretracting pocket tape measure A tape measure or measuring tape is a ribbon of cloth, plastic, or metal with linearmeasure markings, often in both imperial and metric units. ...
The metre (American English:meter) is a measure of length. ...
cm redirects here, alternate uses: cm (disambiguation) A centimetre (symbol cm; American spelling: centimeter) is an SI unit of length. ...
Practical rulers have distance markings along their edges.  The ruler (calibrated, though numbers are not shown) appears as a charge in heraldry, notably in the arms of Odouze.
== Geometric constructions == gfhnkgvjhghg In heraldry, a charge is an image occupying the field on an escutcheon (or shield). ...
Heraldry in its most general sense encompasses all matters relating to the duties and responsibilities of officers of arms. ...
 Main article: Compass and straightedge
In geometry, a ruler usually refers to an unmarked ruler, only used for drawing straight lines between points, not measuring. A ruler and compass construction thus refers to constructions using such unmarked ruler and a compass. It is known for instance, that the angle trisection problem is an impossible one, within the classic restriction of ruler bearing no marks. However, should a single mark be allowed on the ruler, the problem becomes solvable. It is common to call rulers in the geometric context as straightedges. Creating a regular hexagon with a ruler and compass Construction of a regular pentagon Compass and straightedge or rulerandcompass construction is the construction of lengths or angles using only an idealized ruler and compass. ...
Creating a regular hexagon with a ruler and compass Construction of a regular pentagon Compass and straightedge or rulerandcompass construction is the construction of lengths or angles using only an idealized ruler and compass. ...
A number of ancient problems in geometry involve the construction of lengths or angles using only an idealized ruler and compass, or more properly a straightedge and compass. ...
A straightedge is a tool similar to a ruler, but without markings. ...
See also
