|
Measuring Tapes & Rulers
A ruler or rule is an instrument used in geometry, technical drawing and engineering/building to measure distances and/or to rule straight lines. more...
Home
Building & Hardware
Dining & Bar
Electrical & Solar
Food & Wine
Heating, Cooling & Air
Home Security
Kitchen
Major Appliances
Outdoor Power Equipment
Plumbing & Fixtures
Tools
Air Compressors
Air Tools
Flashlights
Generators, Home-Use
Hand Tools
Clamps & Vises
Bar Clamps
Bench, Table Vises
Other Clamps & Vises
Spring & C-Clamps
Files & Chisels
Hammers
Knives & Cutters
Other Knives & Cutters
Pocket Knives & Cutters
Utility Knives & Cutters
Leatherworking Tools
Levels & Plumb Bobs
Laser Levels
Other Levels & Plumb Bobs
Standard Levels
Measuring Tools
Calipers
Measuring Tapes & Rulers
Other Measuring Tools
Squares
Mixed Tool Sets
Other Hand Tools
Planes
Pliers
Other Pliers
Plier Sets
Single Pliers
Pry Bars
Pullers
Punches
Saws
Screwdrivers
Craftsman Sets
Other Screwdriver Sets
Other Screwdrivers
Screwdriver Sets
Single Screwdrivers
Snap-On Sets
Stanley Sets
Winches
Wrenches
Adjustable Wrenches
Allen & Hex Wrenches
Other Wrenches
Pipe Wrenches
Socket Wrenches
Torque Wrenches
Wrench Sets
Meters, Testers & Probes
Other Tools
Power Tools
Safety, Protective Gear
Tie Downs, Straps
Tool Boxes, Belts & Storage
Welding & Soldering Tools
Vacuum Cleaners &...
Wholesale Lots
Window Treatments
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.
Several different designs of flexible instruments are used to determine length, such as the carpenter's rule, the ribbon-like 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 small-sized housing.
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
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 geometric context as straightedges.
Read more at Wikipedia.org
|
|