work, in physics and mechanics, transfer of energy by a force acting to displace a body. Work is equal to the product of the force and the distance through which it produces movement. Although both force and displacement are vector quantities, having both magnitude and direction, work is a scalar quantity, having only magnitude. If the force acts in a direction other than that of the motion of the body, then only that component of the force in the direction of the motion produces work. Thus when a 5-lb (22.4-newton) force pulls a body 10 ft (3 m), it does 50 foot-pounds (67.2 meter-newtons) of work. If a force acts on a body constrained to remain stationary, no work is done by the force. Even if the body is in motion, the force must have a component in the direction of motion. Thus, any centripetal force, such as the sun's gravitational pull on the earth, does no work because it acts at right angles to the motion and has no component in that direction (see centripetal force and centrifugal force). When there is no friction and a force acts on a body, the work done by the force is equal to the increase of the kinetic and potential energy of the body, since all the energy expended by the agency exerting the force must be gained by the body. If frictional forces are present, then some of the work must go to overcome friction and appears finally in the form of heat energy. A simple machine is a device for converting work into another form of energy. For example the jackscrew converts an input of work done on the machine to raise the load. The efficiency of a machine, which is defined as the ratio of the work output to the work input, is always less than one, since some of the input is invariably wasted in overcoming friction. The element of time does not enter into the computation of work; the time rate of doing work is called power. One horsepower is an expenditure of 33,000 foot-pounds per minute. Some of the units used to measure work are the foot-pound, the erg, and the joule.

topiary work, pruning and training of shrubs and trees into ornamental shapes, used in landscape gardening. Elaborate topiary work in which trees and shrubs are clipped to resemble statuary (e.g., birds, nymphs, urns) or are planted to form mazes or intricate geometrical patterns was once popular but now can be seen only in old-fashioned or specialized private gardens or in formal parks and botanical displays. Arborvitae, box, privet, and yew are among the plants most used for topiary gardening. See espalier.

social work, organized effort to help individuals and families to adjust themselves to the community, as well as to adapt the community to the needs of such persons and families.

Modern Social Work

Modern social work employs three methods of assistance: case work, group work, and community organization. Case work is the method by which individual persons and families are assisted. The person in need of case work may be physically, mentally, or socially handicapped. Among those regarded as socially handicapped are: the unemployed, the homeless, members of broken families, alcoholics, drug addicts, and neglected or problem children. To determine the cause of maladjustment, the social worker must understand individual psychology as well as the sociology of the community. Physicians, psychiatrists, and other specialists may be required to help diagnose the difficulty.

Social group work is exemplified by the social settlement, the supervised playground and gymnasium, and the classroom, where handicrafts may be learned. The community may be called upon to provide the buildings and grounds for such activities; often the services of volunteers and of public groups are utilized; in recent years people living in poverty areas have been employed to work in and direct poverty projects in their own communities.

Through community organization the welfare work of single agencies as well as of whole communities is directed, cooperation between public and private agencies is secured, and funds are raised and administered. The funds required by private agencies are often pooled in a community chest, from which each agency receives a share. Community welfare councils are organized to map programs of rehabilitation, to eliminate duplication of services, and to discover and meet overlooked needs.

The Development of Social Work

Social work emerged as a profession out of the early efforts of churches and philanthropic groups to relieve the effects of poverty, to bring the comforts of religion to the poor, to promote temperance and encourage thrift, to care for children, the sick, and the aged, and to correct the delinquent. Orphanages and homes for the elderly were typical results of these activities. The word charity best describes the early activities, which were aimed at the piecemeal alleviation of particular maladjustments. In such charitable work the principal criterion in determining aid to families was worthiness, while the emphasis in later social work was on restoring individuals to normal life both for their own sake and for the sake of the community.

The first attempts to solve the problem of poverty in a modern scientific way was made by P. G. F. Le Play, who in the 1850s made a detailed study of the budgets of hundreds of French workers' families. Forty years later Charles Booth investigated wages and prices, working conditions, housing and health, standards of living, and leisure activities among the poor of London and revealed the extreme poverty of a third of the population. Booth's social survey became a method for determining the extent of social maladjustment, and through surveys in other cities in Europe and the United States a vast number of facts were accumulated, and methods were developed that provided the basis for modern social work.

In 1874 the National Conference of Charities and Correction (now called the National Conference on Social Welfare) was organized in the United States. Public relief and private philanthropic effort remained largely matters of local and state concern until after 1930, when the federal government entered the field of social work on a large scale to cope with the effects of the Great Depression. Resources were made available, the number of social workers was greatly increased, and it became necessary to coordinate public and private activities. Social work has been steadily professionalized, and special graduate schools as well as departments in universities have been established to train social workers. By 1999 there were 377 accredited undergraduate schools of social work in the United States.

drawn work: see lace.

crochet work, form of knitting done with a hook, by means of which loops of thread or yarn are drawn through other, preceding loops. Crochet stitches are all based on the chain or single crochet, i.e., a single loop. In double crochet the thread is thrown once about the hook before the loop is drawn. All other stitches and patterns are merely varying combinations of the single or double loop. The art finds its highest expression in Irish crochet, done with the finest thread and hooks in intricate patterns, usually displaying a motif of leaves or flowers set in an open weblike ground. Whole garments, as well as trimmings, hats, and bags are made by the skillful Irish needlewomen.

Work, Hubert, 1860-1942, American cabinet officer, b. Marion Center, Pa. A practicing physician in Colorado, he became prominent in state and then in national Republican politics. He was Postmaster General (1922-23) under President Harding; then, after the exposure of Albert B. Fall in the Teapot Dome Scandal, succeeded him (1923) as Secretary of the Interior and reorganized the department. He resigned in 1928 and, as Republican national chairman (1928-29), managed Herbert Hoover's successful campaign for the presidency.

Work Projects Administration (WPA), former U.S. government agency, established in 1935 by executive order of President Franklin Delano Roosevelt as the Works Progress Administration; it was renamed the Work Projects Administration in 1939, when it was made part of the Federal Works Agency. Created when unemployment was widespread, the WPA—headed by Harry L. Hopkins until 1938—was designed to increase the purchasing power of persons on relief by employing them on useful projects. WPA's building program included the construction of 116,000 buildings, 78,000 bridges, and 651,000 mi (1,047,000 km) of road and the improvement of 800 airports. Also a part of WPA's diversified activities were the Federal Art Project, the Federal Writers' Project, and the Federal Theatre Project. Close to 10,000 drawings, paintings, and sculptured works were produced through WPA, and many public buildings (especially post offices) were decorated with murals. The experiments in theatrical productions were highly praised and introduced many fresh ideas. Musical performances under the project averaged 4,000 a month. The most notable product of writers in WPA was a valuable series of state and regional guidebooks. WPA also conducted an education program and supervised the activities of the National Youth Administration. At its peak WPA had about 3.5 million persons on its payrolls. Altogether WPA employed a total of 8.5 million persons, and total federal appropriations for the program amounted to almost $11 billion. There was sharp criticism of the WPA in a Senate committee report in 1939; the same year the WPA appropriation was cut, several projects were abolished, and others were curtailed. A strike of thousands of WPA workers to prevent a cut in wages on building projects was unsuccessful. Steadily increasing employment in the private sector, much speeded just before and during World War II, caused further drastic cuts in WPA appropriations and payrolls. In June, 1943, the agency officially went out of existence.

New York School of Social Work: see Columbia Univ.

Cosmati work: see mosaic.

Semiskilled or unskilled workers who move from one region to another, offering their services on a temporary, usually seasonal, basis. In North America, migrant labour is generally employed in agriculture and moves seasonally from south to north following the harvest. In Europe and the Middle East, migrant labour usually involves urban rather than agricultural employment and calls for longer periods of residence. The migrant labour market is often disorganized and exploitative. Many workers are supervised by middlemen such as labour contractors and crew leaders, who recruit and transport them and dispense their pay. Labourers commonly endure long hours, low wages, poor working conditions, and substandard housing. In some countries, child labour is widespread among migrant labourers, and even in the U.S. those children who do not work often do not go to school, since schools are usually open only to local residents. Workers willing to accept employment on these terms are usually driven by even worse conditions in their home countries. Labour organizing is made difficult by mobility and by low rates of literacy and political participation, though some migrant labourers in the U.S. have been unionized. Seealso Cesar Chavez.

Learn more about migrant labour with a free trial on Britannica.com.

Association of workers in a particular trade, industry, or plant, formed to obtain improvements in pay, benefits, and working conditions through collective action. The first fraternal and self-help associations of labourers appeared in Britain in the 18th century, and the era of modern labour unions began in Britain, Europe, and the U.S. in the 19th century. The movement met with hostility from employers and governments, and union organizers were regularly prosecuted. British unionism received its legal foundation in the Trade-Union Act of 1871. In the U.S. the same effect was achieved more slowly through a series of court decisions that whittled away at the use of injunctions and conspiracy laws against unions. The founding of the American Federation of Labor (AFL) in 1886 marked the beginning of a successful, large-scale labour movement in the U.S. The unions brought together in the AFL were craft unions, which represented workers skilled in a particular craft or trade. Only a few early labour organizers argued in favour of industrial unions, which would represent all workers, skilled or unskilled, in a single industry. The Congress of Industrial Organizations (CIO) was founded by unions expelled from the AFL for attempting to organize unskilled workers, and by 1941 it had assured the success of industrial unionism by organizing the steel and automotive industries (see AFL-CIO). The use of collective bargaining to settle wages, working conditions, and disputes is standard in all noncommunist industrial countries, though union organization varies from country to country. In Britain, labour unions displayed a strong inclination to political activity that culminated in the formation of the Labour Party in 1906. In France, too, the major unions became highly politicized; the Confédération Générale du Travail (formed in 1895) was allied with the Communist Party for many years, while the Confédération Française Démocratique du Travail is more moderate politically. Japan developed a form of union organization known as enterprise unionism, which represents workers in a single plant or multiplant enterprise rather than within a craft or industry.

Learn more about labour union with a free trial on Britannica.com.

Body of law that applies to matters such as employment, wages, conditions of work, labour unions, and labour-management relations. Laws intended to protect workers, including children, from abusive employment practices were not enacted in significant numbers until the late 19th century in Europe and slightly later in the U.S. In Asia and Africa, labour legislation did not emerge until the 1940s and '50s. Employment laws cover matters such as hiring, training, advancement, and unemployment compensation. Wage laws cover the forms and methods of payment, pay rates, social security, pensions, and other matters. Legislation on working conditions regulates hours, rest periods, vacations, child labour, equality in the workplace, and health and safety. Laws on trade unions and labour-management relations address the status of unions, the rights and obligations of workers' and employers' organizations, collective bargaining agreements, and rules for settling strikes and other disputes. Seealso arbitration; mediation.

Learn more about labour law with a free trial on Britannica.com.

Study of how workers are allocated among jobs, how their rates of pay are determined, and how their efficiency is affected by various factors. The labour force of a country includes all those who work for gain in any capacity as well as those who are unemployed but seeking work. Many factors influence how workers are utilized and how much they are paid, including qualities of the labour force itself (such as health, level of education, distribution of special training and skills, and degree of mobility), structural characteristics of the economy (e.g., proportions of heavy manufacturing, technology, and service industries), and institutional factors (including the extent and power of labour unions and employers' associations and the presence of minimum-wage laws). Miscellaneous factors such as custom and variations in the business cycle are also considered. Certain general trends are widely accepted by labour economists; for instance, wage levels tend to be higher in jobs that involve high risk, in industries that require higher levels of education or training, in economies that have high proportions of such industries, and in industries that are heavily unionized.

Learn more about labour economics with a free trial on Britannica.com.

In economics, the general body of wage earners. In classical economics, labour is one of the three factors of production, along with capital and land. Labour can also be used to describe work performed, including any valuable service rendered by a human agent in the production of wealth, other than accumulating and providing capital. Labour is performed for the sake of its product or, in modern economic life, for the sake of a share of the aggregate product of the community's industry. The price per unit of time, or wage rate, commanded by a particular kind of labour in the market depends on a number of variables, such as the technical efficiency of the worker, the demand for that person's particular skills, and the supply of similarly skilled workers. Other variables include training, experience, intelligence, social status, prospects for advancement, and relative difficulty of the work. All these factors make it impossible for economists to assign a standard value to labour. Instead, economists often quantify labour hours according to the quantity and value of the goods or services produced.

Learn more about labour with a free trial on Britannica.com.

Specialization in the production process. Complex jobs can usually be less expensively completed by a large number of people each performing a small number of specialized tasks than by one person attempting to complete the entire job. The idea that specialization reduces costs, and thereby the price the consumer pays, is embedded in the principle of comparative advantage. Division of labour is the basic principle underlying the assembly line in mass production systems. See Émile Durkheim.

Learn more about division of labour with a free trial on Britannica.com.

Employment of boys and girls in occupations deemed unfit for children. Such labour is strictly controlled in many countries as a result of the effective enforcement of laws passed in the 20th century (e.g., the United Nations Declaration of the Rights of the Child in 1959). In developing nations the use of child labour is still common. Restrictive legislation has proved ineffective in impoverished societies with few schools, although some improvements have resulted from global activism, such as boycotts of multinational firms alleged to be exploiting child labour abroad.

Learn more about child labour with a free trial on Britannica.com.

Value attached to hard work, thrift, and self-discipline under certain Protestant doctrines, particularly those of Calvinism. Max Weber, in The Protestant Ethic and the Spirit of Capitalism (1904–05), held that the Protestant ethic was an important factor in the economic success of Protestant groups in the early stages of European capitalism, in that worldly success came to be interpreted as a sign of the individual's election to eternal salvation. Weber's thesis was variously criticized and expanded throughout the 20th century. Seealso Protestantism; Richard H. Tawney.

Learn more about Protestant ethic with a free trial on Britannica.com.

In physics, the measure of energy transfer that occurs when an object is moved over a distance by an external force, some component of which is applied in the direction of displacement. For a constant force, work math.W is equal to the magnitude of the force math.F times the displacement math.d of the object, or math.W = math.Fmath.d. Work is also done by compressing a gas, by rotating a shaft, and by causing invisible motions of particles within a body by an external magnetic force. No work is accomplished by simply holding a heavy stationary object, because there is no transfer of energy and no displacement. Work done on a body is equal to the increase in energy of the body. Work is expressed in units called joules (J). One joule is equivalent to the energy transferred when a force of one newton is applied over a distance of one metre.

Learn more about work with a free trial on Britannica.com.

or muqarnas

Honeycomb-like Islamic architectural ornamentation formed by the intricate corbeling (see corbel) of squinches (see Byzantine architecture), brackets, and inverted pyramids in overlapping tiers. It appeared in the early 12th century throughout the Islamic world; a frequent use was to overlay the transitional zone between domes and their supports. It reached its highest development in the 14th–15th century, when it became the usual decoration for door heads, niches, and the bracketing under cornices and minaret galleries. Rich examples are found in the Alhambra and other Moorish works in Spain.

Learn more about stalactite work with a free trial on Britannica.com.

also called social work

Any of various professional activities or methods concerned with providing social services (such as investigatory and treatment services or material aid) to disadvantaged, distressed, or vulnerable persons or groups. The field originated in the charity organizations in Europe and the U.S. in the late 19th century. The training of volunteer workers by these organizations led directly to the founding of the first schools of social work and indirectly to increased government responsibility for the welfare of the disadvantaged. Social service providers may serve the needs of children and families, the poor or homeless, immigrants, veterans, the mentally ill, the handicapped, victims of rape or domestic violence, and persons dependent on alcohol or drugs. Seealso welfare.

Learn more about social service with a free trial on Britannica.com.

In the U.S., any state law forbidding various union-security measures, particularly the union shop, under which workers are required to join a union within a specified time after they begin employment. Supporters of such laws maintain that they are more equitable because they allow a person to choose whether or not to join a labour union. Opponents contend that the name right-to-work law is misleading because such laws do not guarantee employment to anyone. On the contrary, they maintain that such laws tend to reduce workers' job security by weakening the bargaining power of unions.

Learn more about right-to-work law with a free trial on Britannica.com.

Type of embroidery in which the stitches are counted and worked with a needle over the threads, or mesh, of a canvas foundation. It was known as canvas work until the early 19th century. If the canvas has 16 or more mesh holes per linear inch, the embroidery is called petit point; most needlepoint was petit point in the 16th–18th century. Needlepoint as it is known today originated in the 17th century, when the fashion for furniture upholstered with embroidered fabrics prompted the development of a more durable material to serve as the embroidery's foundation. Wool is generally used for needlepoint, silk yarn less often. Needlepoint kits, containing canvas stamped with a design and all the materials needed for the project, were sold as early as the mid-18th century. Seealso bargello.

Learn more about needlepoint with a free trial on Britannica.com.

in full Works Progress Administration later (1939–43) Work Projects Administration

U.S. work program for the unemployed. Created in 1935 under the New Deal, it aimed to stimulate the economy during the Great Depression and preserve the skills and self-respect of unemployed persons by providing them useful work. During its existence, it employed 8.5 million people in the construction of 650,000 mi (1,046,000 km) of roads, 125,000 public buildings, 75,000 bridges, 8,000 parks, and 800 airports. The WPA also administered the WPA Federal Art Project, the Theater Project, and the Writers' Project, which provided jobs for unemployed artists, actors, and writers. In 1943, with the virtual elimination of unemployment by the wartime economy, the WPA was terminated.

Learn more about WPA with a free trial on Britannica.com.

Type of decorative inlay or mosaic used by Roman decorators and architects in the 12th–13th centuries. Small pieces of coloured stone and glass were combined with strips and disks of white marble arranged in geometric patterns. Cosmati work was used for architectural decoration and church furnishings. The term derives from craftsmen of several families named Cosmatus.

Learn more about Cosmati work with a free trial on Britannica.com.