Mother's Day and Father's Day Holidays. In the U.S. a nation¬ wide observance of Mother’s Day was suggested by Anna Jarvis of Grafton, W.Va., and in 1908 formal observances were held in churches in Grafton and Philadelphia. By 1911 every state celebrated the occasion on the second Sunday in May. It was formalized by Congress in 1914. In Britain, Mother’s Day is celebrated in mid-Lent as Mothering Sunday. During the Middle Ages a custom developed of allowing those who had moved away to visit their home parishes and their mothers on Laetare Sunday, the fourth Sunday of Lent. Many other countries also celebrate the holiday on this date, while some mark the observance at other times of the year. Father’s Day was first celebrated in 1910 in Spokane, Wash., through efforts of Sonora Dodd and the YMCA. Celebrated on the third Sunday in June, it became a legal holiday in 1972. Both days were origi¬ nally largely religious holidays but have been commercialized with the sending of greeting cards and the giving of gifts.
Motherwell, Robert (b. Jan. 24, 1915, Aberdeen, Wash., U.S.—d. July 16, 1991, Provincetown, Mass.)
U.S. painter, writer, and teacher. He received an art scholarship at 11, but he earned degrees from Stanford and Harvard before deciding to become a serious painter. He espoused Abstract Expressionism from the beginning of his career, and his eru¬ dite writings were largely respon¬ sible for the intellectual tone of the movement. In his Elegy to the Span¬ ish Republic painting series, begun in 1949 and continued over three decades, he developed a limited rep¬ ertory of simple, serene black forms that were applied to the picture plane in a way that created a sense of slow, solemn movement. Though he worked in various styles, his reputa¬ tion rests on his pioneering work as a founder and principal exponent of Abstract Expressionism.
Motherwell, photograph by Arnold Newman, 1959
©ARNOLD NEWMAN
motion Change in position of a body relative to another body or with respect to a frame of reference or coordinate system. Motion occurs along a definite path, the nature of which determines the character of the motion. Translational motion occurs if all points in a body have similar paths rela¬ tive to another body. Rotational motion occurs when any line on a body changes its orientation relative to a line on another body. Motion relative to a moving body, such as motion on a moving train, is called relative motion. Indeed, all motions are relative, but motions relative to the Earth or to any body fixed to the Earth are often assumed to be absolute, as the effects of the Earth’s motion are usually negligible. See also Brownian MOTION; PERIODIC MOTION; SIMPLE HARMONIC MOTION; SIMPLE MOTION; UNIFORM CIR¬ CULAR MOTION.
motion, equation of Mathematical formula that describes the motion of a body relative to a given frame of reference, in terms of the position, velocity, or acceleration of the body. In classical mechanics, the basic equa¬ tion of motion is Newton’s second law (see Newton's laws of motion), which relates the force on a body to its mass and acceleration. When the force is described in terms of the time interval over which it is applied, the velocity and position of the body can be derived. Other equations of motion include the position-time equation, the velocity-time equation, and the acceleration-time equation of a moving body.
motion picture or movie Series of still photographs on film, pro¬ jected in rapid succession onto a screen. Motion pictures are filmed with a movie camera, which makes rapid exposures of people or objects in motion, and shown with a movie projector, which reproduces sound syn¬ chronized with the images. The principal inventors of motion-picture machines were Thomas Alva Edison in the U.S. and the Lumiere brothers in France. Film production was centred in France in the early 20th century, but by 1920 the U.S. had become dominant. As directors and stars moved to Hollywood, movie studios expanded, reaching their zenith in the 1930s and ’40s, when they also typically owned extensive theatre chains. Mov¬ iemaking was marked by a new internationalism in the 1950s and ’60s, which also saw the rise of the independent filmmaker. The sophistication of special effects increased greatly from the 1970s. The U.S. film indus¬ try, with its immense technical resources, has continued to dominate the world market to the present day. See also Columbia Pictures; MGM; Para¬ mount Communications; RKO; United Artists; Warner Brothers.
motion sickness Sickness caused by contradiction between external data from the eyes and internal cues from the balance centre in the inner ear. For example, in seasickness the inner ear senses the ship’s motion, but the eyes see the still cabin. This stimulates stress hormones and accel¬ erates stomach muscle contraction, leading to dizziness, pallor, cold sweat, and nausea and vomiting. Minimizing changes of speed and direc¬ tion may help, as may reclining, not turning the head, closing the eyes, or focusing on distant objects. Drugs can prevent or relieve motion sick¬ ness but may have side effects. Pressing an acupuncture point on the wrist helps some people.
motion study See time-and-motion study
motivation Factors within a human being or animal that arouse and direct goal-oriented behaviour. Motivation has long been a central sub¬ ject of study in psychology. Early researchers, influenced by Charles Dar¬ win, ascribed much of animal and human behaviour to instinct. Sigmund Freud believed that much of human behaviour was also based on irratio¬ nal instinctive urges or unconscious motives. Walter B. Cannon proposed that basic human drives served homeostatic functions by directing ener¬ gies toward the reduction of physiological tensions. Behavioral psycholo¬ gists, in contrast, stress the importance of external goals in prompting action, while humanistic psychologists examine the role of felt needs. Cognitive psychologists have found that a motive sensitizes a person to information relating to that motive: a hungry subject, for example, will perceive food stimuli as larger than other stimuli. See also behaviour genet¬ ics; HUMAN NATURE; LEARNING.
Motley, Marion (b. June 5, 1920,
1999, Cleveland, Ohio,) U.S. gridiron and linebacker for South Carolina State University and the University of Nevada. In 1946 he helped deseg¬ regate professional football by join¬ ing the Cleveland Browns as a fullback. A bruising rusher, he estab¬ lished himself as a running back and helped the Browns to five consecu¬ tive league championships (All- American Football Conference,
1946-49; NFL, 1950).
motocross Form of motorcycle racing in which cyclists compete on a closed course marked out over natural or simulated rough terrain.
Courses vary widely but must be 1.5-5 km (1-3 mi) in length, with steep inclines, hairpin turns, and mud. Motorcycles are grouped into
Leesburg, Ga., U.S.—d. June 27, football player. He played fullback
Motocross racing
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classes according to engine displacement (e.g., 125-, 250-, 500-cc). It is probably the most physically demanding motorcycle sport.
Motoori Norinaga N.mo-to-'o-re-.no-re-'na-gaN (b. June 21, 1730, Matsuzaka, Japan—d. Nov. 5, 1801, Matsuzaka) Japanese Shinto scholar. Trained as a physician, he came under the influence of the Kokugaku movement, which stressed the importance of Japan’s literary heritage. The critical methods he used in his commentaries on Japanese classics pro¬ vided the theoretical foundation of the modern Shinto revival. Rejecting Buddhist and Confucian interpretations, he traced the genuine spirit of Shinto to Japanese myths and sacred traditions. He reaffirmed the ancient Japanese concept of musubi (the mysterious power of all creation and growth), which has become one of the main tenets of modern Shinto.