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velocity
ve·loc·i·ty V0048400 (və-lŏs′ĭ-tē)n. pl. ve·loc·i·ties 1. Rapidity or speed of motion; swiftness.2. Physics A vector quantity whose magnitude is a body's speed and whose direction is the body's direction of motion.3. a. The rate of speed of action or occurrence.b. The rate at which money changes hands in an economy.
[Middle English velocite, from Old French, from Latin vēlōcitās, from vēlōx, vēlōc-, fast; see weg- in Indo-European roots.]velocity (vɪˈlɒsɪtɪ) n, pl -ties1. speed of motion, action, or operation; rapidity; swiftness2. (Units) physics a measure of the rate of motion of a body expressed as the rate of change of its position in a particular direction with time. It is measured in metres per second, miles per hour, etc. Symbol: u, v or w 3. physics (not in technical usage) another word for speed3[C16: from Latin vēlōcitās, from vēlōx swift; related to volāre to fly]ve•loc•i•ty (vəˈlɒs ɪ ti)
n., pl. -ties. 1. rapidity of motion, action, or operation; swiftness; speed. 2. Mech. the time rate of change of position of a body in a specified direction. [1540–50; < Latin vēlōcitās speed. See velocipede, -ty2] syn: See speed. ve·loc·i·ty (və-lŏs′ĭ-tē) The rate at which an object moves in a specified direction.Usage We normally think of velocity as the speed at which an object is traveling. But in physics, velocity and speed are not the same. Like speed, velocity refers to the rate at which an object is moving—the distance per unit of time. But velocity in physics also includes the direction in which the object is moving, whereas direction has no bearing on an object's speed. For example, if two cars were driving at a rate of 50 miles per hour, and both headed due north, you could rightly say that they were both traveling at the same speed and at the same velocity. But if one of the cars were to turn west at a certain point, continuing at the same rate of 50 miles per hour, you could only say that they were traveling at the same speed, not at the same velocity. Similarly, traveling around a curve, a car may maintain the same speed throughout, but its velocity will be constantly changing. This change in velocity over time is called acceleration.velocityRate of motion in a particular direction.Thesaurus| Noun | 1. |  velocity - distance travelled per unit time speedangular velocity - (physics) the rate of change of the angular position of a rotating body; usually expressed in radians per second or radians per minuteairspeed - the speed of an aircraft relative to the air in which it is flyingescape velocity - the minimum velocity needed to escape a gravitational fieldgroundspeed - the speed of an aircraft relative to the groundhypervelocity - excessive velocity; "the meteorites struck the earth with hypervelocity impacts"muzzle velocity - the velocity of a projectile as it leaves the muzzle of a gunpeculiar velocity - velocity with respect to the local standard of restradial velocity - velocity along the line of sight toward or away from the observerlight speed, speed of light, c - the speed at which light travels in a vacuum; the constancy and universality of the speed of light is recognized by defining it to be exactly 299,792,458 meters per secondsteerageway - (nautical) the minimum rate of motion needed for a vessel to be maneuveredterminal velocity - the constant maximum velocity reached by a body falling through the atmosphere under the attraction of gravityrate - a magnitude or frequency relative to a time unit; "they traveled at a rate of 55 miles per hour"; "the rate of change was faster than expected" |
velocitynoun speed, pace, rapidity, quickness, swiftness, fleetness, celerity the velocity at which the planets orbitvelocitynounRate of motion or performance:pace, speed, tempo.Informal: clip.Translationsvelocity (vəˈlosəti) noun speed, especially in a given direction. 速度 速度velocity
velocity, change in displacement with respect to time. Displacement is the vectorvector,
quantity having both magnitude and direction; it may be represented by a directed line segment. Many physical quantities are vectors, e.g., force, velocity, and momentum.
..... Click the link for more information. counterpart of distance, having both magnitude and direction. Velocity is therefore also a vector quantity. The magnitude of velocity is known as the speed of a body. The average velocity or average speed of a moving body during a time period t may be computed by dividing the total displacement or total distance by t. Computation of the instantaneous velocity at a particular moment, however, usually requires the methods of the calculus.Velocity The time rate of change of position of a body in a particular direction. Linear velocity is velocity along a straight line, and its magnitude is commonly measured in such units as meters per second (m/s), feet per second (ft/s), and miles per hour (mi/h). Since both a magnitude and a direction are implied in a measurement of velocity, velocity is a directed or vector quantity, and to specify a velocity completely, the direction must always be given. The magnitude only is called the speed. See Speed A body need not move in a straight line path to possess linear velocity. When a body is constrained to move along a curved path, it possesses at any point an instantaneous linear velocity in the direction of the tangent to the curve at that point. The average value of the linear velocity is defined as the ratio of the displacement to the elapsed time interval during which the displacement took place. The representation of angular velocity ω as a vector is shown in the illustration. The vector is taken along the axis of spin. Its length is proportional to the angular speed and its direction is that in which a right-hand screw would move. If a body rotates simultaneously about two or more rectangular axes, the resultant angular velocity is the vector sum of the individual angular velocities.  Angular velocity shown as an axial vectorVelocity in mechanics, a kinematic quantity characterizing the motion of a point. Strictly speaking, velocity is a vector quantity and thus has both a magnitude and a direction. The magnitude, a scalar quantity, is known as speed. The term “velocity,” however, is sometimes loosely used in the sense of “speed.” For a point in uniform motion, its speed v is equal to the ratio of the distance s traversed to the time t in which this distance is traveled—that is, v = s/t. In the general case, the instantaneous speed of a point is v = ds/dt, and the instantaneous velocity is v = dr/dt, where r is the radius vector of the point. The velocity vector is directed along the tangent to the point’s trajectory. If the motion of the point is defined by equations that express the dependence of the point’s Cartesian coordinates x, y, and z on the time t, then 
where vx = dx/dt, vy= dy/dt, and vz = dz/dt. The cosines of the angles formed by the velocity vector and the coordinate axes are equal to vx/vx vy/vz and vz/v, respectively. velocity[və′läs·əd·ē] (mechanics) The time rate of change of position of a body; it is a vector quantity having direction as well as magnitude. Also known as linear velocity. The speed at which the detonating wave passes through a column of explosives, expressed in meters or feet per second. velocityThe rate of change of position in a given direction.velocity Physics a measure of the rate of motion of a body expressed as the rate of change of its position in a particular direction with time. It is measured in metres per second, miles per hour, etc.
See velocityvelocity
ve·loc·i·ty (v), (vĕ-los'i-tē), Rate of movement; specifically, distance traveled or quantity converted per unit time in a given direction. Compare: speed. [L. velocitas, fr. velox (veloc-), quick, swift] velocity An MRI term for the speed of a thing in a particular direction.velocity The rate of a body's motion in a given direction per unit of time; speed Ballistics The speed that a projectile/bullet attains while in flight; the difference in tissue destruction between high- or low-velocity bullets is caused by the fragmentation of the bullet–as occurs in an M-16 semiautomatic weapon, rather than the speed of the bullet. See Ballistics, Critical velocity. ve·loc·i·ty (v) (vĕ-los'i-tē) Rate and direction of movement; specifically, distance traveled or quantity converted per unit time in a given direction. [L. velocitas, fr. velox (veloc-), quick, swift]ve·loc·i·ty (vĕ-los'i-tē) Rate and direction of movement. [L. velocitas, fr. velox (veloc-), quick, swift]Velocity
VelocityThe number of times a dollar is spent, or turns over, in a specific period of time. Velocity affects the amount of economic activity generated by a given money supply.Velocity of MoneyThe rate at which money changes hands. For example, assume an economy with $100 and two people in it. In a given year, if Person A charges Person B $50 for a widget, and Person B charges Person A $100 for a whatsit, then $150 worth of transaction has occurred even though there are only $100 in the economy. This means that, on average, one dollar is spent one and a half times in a year, expressed as a velocity of 1.5/year. Velocity of money is useful as a measure of how strong and/or liquid an economy is, and it is usually compared with some figure such as GDP or money supply.See VLCTY
See VLCTYvelocity
Synonyms for velocitynoun speedSynonyms- speed
- pace
- rapidity
- quickness
- swiftness
- fleetness
- celerity
Synonyms for velocitynoun rate of motion or performanceSynonymsSynonyms for velocitynoun distance travelled per unit timeSynonymsRelated Words- angular velocity
- airspeed
- escape velocity
- groundspeed
- hypervelocity
- muzzle velocity
- peculiar velocity
- radial velocity
- light speed
- speed of light
- c
- steerageway
- terminal velocity
- rate
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