# Read the text and name the basic types of motions.

Mechanisms are used to convert between one type of motion and another. Any machine can be looked on as a group of interconnected mechanisms which convert one type of motion to a variety of other motions. These changes may be to convert rotary motion to straight line motion or to convert reciprocal (back and forth) motion to intermittent motion. They may also transform a fixed type of motion, for example by magnifying a linear motion or by slowing down a rotary motion. Here, motions are divided into six basic types: linear, reciprocating, rotary, oscillation, intermittent, and irregular.

Linear motionis the most basic of all motions. Uninterrupted objects will continue to move in a straight line indefinitely. Under every day circumstances gravity and friction conspire to bring objects to rest. Linear motion is measured in two parts: speed and direction. Together these make up the velocity. Linear motion is not often used as a starting point for mechanisms.

Rotary motion is motion in a circle. It is the starting point for many mechanisms. Rotary motion is measured in either angular velocity, the number of degrees turned in a given time, or in revolutions per minute (rpm). The direction of turn, either clockwise or anti-clockwise is also part of the measurement of rotary motion. The strength of rotary motion is known as the torque, the turning force.

Intermittent motionis motion which starts and stops regularly. Intermittent motion is usually the end result of a mechanism rather than the starting point for conversion.

Reciprocating motionis back and forth motion. Reciprocating motion is measured by its throw (the distance between the two extremes of motion) and by its period (the length of time for each cycle).

Oscillationis back and forth motion about a pivot point. It is measured in terms of both the angle of throw (amplitude) and the period of time for one complete cycle (periodic time) or the number of cycles in a given time (frequency). Oscillation tends to be an ending point for a mechanism rather than the starting point, however some mechanisms are available to convert or transform oscillations.

Irregular motionis motion which has no obvious pattern to its movement. It is often needed in automata to recreate the movements of living things.Irregular motion is usually created using a cam or series of cams. Irregular motion is not often used as the starting point for a mechanism.

6. Find the following words and phrases in English in the text: перетворювати один вид руху на інший; група взаємопов’язаних механізмів; обертальний рух; прямолінійний рух; зворотно-поступальний рух; переривчастий рух; фіксований вид руху; гойдання; нерегулярний; безперервні об’єкти; невпинно; за повсякденних обставин; об’єднувати зусилля; призводити до зупинки об’єктів; кількість обертів та напрям; швидкість; відправна точка; рух по колу; кутова швидкість; колові обертання за хвилину; за годинниковою стрілкою чи проти; вимір; сила обертів; трансформування; рух вперед-назад; хід або розмах; точка обертання; кут розмаху; повний цикл; в певний час; кінцева точка; явна модель; автомат; відтворювати рухи живих створінь.

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