Tearing is the act of breaking apart a material by force, without the aid of a

cutting tool In the context of machining, a cutting tool or cutter is typically a hardened metal tool that is used to cut, shape, and remove material from a workpiece by means of machining tools as well as abrasive tools by way of shear deformation. The major ...

. A tear in a piece of

paper Paper is a thin sheet material produced by mechanically or chemically processing cellulose fibres derived from wood, rags, grasses or other vegetable sources in water, draining the water through fine mesh leaving the fibre evenly distributed ...

fabric Textile is an umbrella term that includes various fiber-based materials, including fibers, yarns, filaments, threads, different fabric types, etc. At first, the word "textiles" only referred to woven fabrics. However, weaving is not the ...

, or some other similar object may be the result of the intentional effort with one's bare hands, or be accidental. Unlike a

cut Cut may refer to: Common uses * The act of cutting, the separation of an object into two through acutely-directed force ** A type of wound ** Cut (archaeology), a hole dug in the past ** Cut (clothing), the style or shape of a garment ** Cut (ea ...

, which is generally on a straight or patterned line controlled by a tool such as

scissors Scissors are hand-operated shearing tools. A pair of scissors consists of a pair of metal blades pivoted so that the sharpened edges slide against each other when the handles (bows) opposite to the pivot are closed. Scissors are used for cutti ...

, a tear is generally uneven and, for the most part, unplanned. An exception is a tear along a perforated line, as found on a roll of

toilet paper Toilet paper (sometimes called toilet tissue or bathroom tissue) is a tissue paper product primarily used to clean the anus and surrounding anal region of feces after defecation, and to clean the perineal area and external genitalia of u ...

paper towel A paper towel is an absorbent, disposable towel made from paper. In Britain, paper towels for kitchen use are also known as kitchen rolls, kitchen paper, or kitchen towels. For home use, paper towels are usually sold in a roll of perforated shee ...

s, which has been previously partially cut, so the effort of tearing will probably produce a straight line. Materials vary in their susceptibility to tearing. Some materials may be quite resistant to tearing when they are in their full form, but when a small cut or tear is made, the material becomes compromised, and the effort needed to continue tearing along that line becomes less. Materials can be characterized by standard

test method A test method is a method for a test in science or engineering, such as a physical test, chemical test, or statistical test. It is a definitive procedure that produces a test result. In order to ensure accurate and relevant test results, a test met ...

s to measure their

tear resistance Tear resistance (or tear strength) is a measure of how well a material can withstand the effects of tearing. It is a useful engineering measurement for a wide variety of materials by many different test methods. Discussion For example, with rubbe ...

. There are several applicable standards which vary around the world. The variables which affect the tear strength can be summarized neatly by the quote: "''The value of tear strength obtained depends on the shape of the test piece, speed of stretching and temperature of test.''"

References

Solid mechanics {{material-stub

See also

References