ratio of word probabilities predicted from brain for hammer and pliers

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hammer

pliers

top 10 words in brain distribution (in article):
steel handle head cut tool nail design hammer shape size
top 10 words in brain distribution (in article):
head steel cut design hand handle metal tool material plate
top 10 words in brain distribution (not in article):
iron blade hair metal whip breast century bronze knife sword
top 10 words in brain distribution (not in article):
iron blade key type lock state century size switch shape
times more probable under hammer 30 20 10 6 4 2.5 1.25 1 1.25 2.5 4 6 10 20 30 times more probable under pliers
(words not in the model)
A hammer'" is a tool meant to deliver an impact to an object. The most common uses are for driving nails, fitting parts, and breaking up objects. Hammers are often designed for a specific purpose, and vary widely in their shape and structure. Usual features are a handle and a head, with most of the weight in the head. The basic design is hand-operated, but there are also many mechanically operated models for heavier uses. The hammer is a basic tool of many professions, and can also be used as a weapon. By analogy, the name "'hammer'" has also been used for devices that are designed to deliver blows, e.g. in the caplock mechanism of firearms. History. The use of simple tools dates to about 2,400,000 BCE when various shaped stones were used to strike wood, bone, or other stones to break them apart and shape them. Stones attached to sticks with strips of leather or animal sinew were being used as hammers by about 30,000 BCE during the middle of the Paleolithic Stone Age. Its archeological record means it is perhaps the oldest human tool known. Designs and variations. The essential part of a hammer is the head, a compact solid mass that is able to deliver the blow to the intended target without itself deforming. The opposite side of a ball as in the ball-peen hammer and the cow hammer. Some upholstery hammers have a magnetized appendage, to pick up tacks. In the hatchet the hammer head is secondary to the cutting edge of the tool. In recent years the handles have been made of durable plastic or rubber. The hammer varies at the top, some are larger than others giving a larger surface area to hit different sized nails and such, Mechanically-powered hammers often look quite different from the hand tools, but nevertheless most of them work on the same principle. They include: In professional framing carpentry, the hammer has almost been completely replaced by the nail gun. In professional upholstery, its chief competitor is the staple gun. Hammer as a force amplifier. A hammer is basically a force amplifier that works by converting mechanical work into kinetic energy and back. In the History. Pliers in the general sense are an ancient and simple invention, no singular point in history or singular inventor can be credited. Early metal working processes from several millennia BC would have required plier-like devices to handle hot materials in the process of smithing or casting. Development from wooden to bronze pliers would have probably happened sometime prior to 3000 BC. Among the oldest illustrations of pliers are those showing the Greek god Hephaestus in his smithy. Today, pliers intended principally to be used for safely handling hot objects are usually called tongs. The number of different designs of pliers grew with the invention of the different objects which they were used to handle: horse shoes, fasteners, wire, pipes, electrical and electronic components. Design. The basic design of pliers has changed little since their origins, with the pair of "handles", the "pivot" (often formed by a rivet), and the "head" section with the gripping jaws or cutting edges forming the three elements. In distinction to a pair of scissors or shears, the plier's jaws always meet each other at one pivot angle. Pliers are an instrument that convert a power grip—the curling of the fingers into the palm of the hand—into a precision grip, directing the power of the hand's grip in a precise fashion on to the objects to be gripped. The handles are long relative to the shorter nose of the pliers. The two arms thus act as first class levers with a mechanical advantage, increasing the force applied by the hand's grip and concentrating it on the work piece. The materials used to make pliers consist mainly of steel alloys with additives such as vanadium or chromium, to improve alloy strength and prevent corrosion. Often pliers have insulated grips to ensure better handling and prevent electrical conductivity. In some lines of fine work (such as jewellery or musical instrument repair), some specialised pliers feature a layer of comparatively soft metal (such as brass) over the two plates of the head of the pliers to reduce pressure placed on some fine tools or materials. Making entire pliers out of softer metals would be impractical, reducing the strength required to break or bend them.