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proper motion
proper motion in astronomy, apparent movement of a star on the celestial sphere , usually measured as seconds of arc per year; it is due both to the actual relative motions of the sun and the star through space. Proper motion reflects only transverse motion, i.e., the component of motion across... Read more |
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inertia
inertia , in physics, the resistance of a body to any alteration in its state of motion , i.e., the resistance of a body at rest to being set in motion or of a body in motion to any change of speed or change in direction of motion. Inertia is a property common to all matter. This property was first... Read more |
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motion
motion the change of position of one body with respect to another. The rate of change is the speed of the body. If the direction of motion is also given, then the velocity of the body is determined; velocity is a vector quantity, having both magnitude and direction, while speed is a scalar... Read more |
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dynamics
dynamics branch of mechanics that deals with the motion of objects; it may be further divided into kinematics, the study of motion without regard to the forces producing it, and kinetics, the study of the forces that produce or change motion. Motion is caused by an unbalanced force acting on... Read more |
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Newtons laws of motion
Newton's laws of motion Three laws published in 1687 by I.Newton concerning the motion of bodies:1.A body continues in a state of uniform rest or motion unless acted upon by an external force.2.The acceleration produced when a force acts is directly proportional to the force and takes place in the... Read more |
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motion sickness
motion sickness waves of nausea and vomiting experienced by some people, resulting from the sudden changes in movement of a vehicle. The ailment is also known as seasickness, car sickness, train sickness, airsickness, and swing sickness. The principal cause of the disturbance is the effect of... Read more |
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Wave motion
WAVE MOTION CONCEPT Wave motion is activity that carries energy from one place to another without actually moving any matter. Studies of wave motion are most commonly associated with sound or radio transmissions, and, indeed, these are among the most common forms of wave... Read more |
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cam
cam mechanical device for converting a rotating motion into a reciprocating, or back-and-forth, motion, or for changing a simple motion into a complex one. A simple form of cam is a circular disk set eccentrically on a shaft in order to induce (when the shaft rotates) a rising and falling motion in... Read more |
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Oscillation
OSCILLATION CONCEPT When a particle experiences repeated movement about a position of stable equilibrium, or balance, it is said to be in harmonic motion, and if this motion is repeated at regular intervals, it is called periodic motion. Oscillation is a type of harmonic... Read more |
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vertical air motion
vertical air motion In contrast to horizontal air motion (i.e. wind), vertical motion is both difficult to measure and is typically of very small magnitude. As a weather-producing agent, however, it is the key to differences between sunny conditions or cloud and rain. Air may ascend or descend for... Read more |
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Small-screen smorgasbord
...Coach''-This series from Barry Kemp (``Newhart'') starring Craig...Billy Dee Williams as Gale Sayers, Jack Warden as George Halas and Abe Gibron...Roseanne and Tom Arnold in ``Backfield in Motion.'' Six mediocre-to-awful... |