Ballistics

the study of the flight path of an object which is being influenced by GRAVITY as it moves. It is applied to bullets, rockets, missiles etc.

Taken from Dictionary of Science

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Ballistics (gr. βάλλειν ('ba'llein'), "throw") is the science of mechanics that deals with the flight, behavior, and effects of projectiles, especially bullets, gravity bombs, rockets, or the like; the science or art of designing and accelerating projectiles so as to achieve a desired performance.

A ballistic body is a body which is free to move, behave, and be modified in appearance, contour, or texture by ambient conditions, substances, or forces, as by the pressure of gases in a gun, by rifling in a barrel, by gravity, by temperature, or by air particles. A ballistic missile is a missile only guided during the relatively brief initial powered phase of flight and its course is subsequently governed by the laws of classical mechanics.

In the field of forensic science, forensic ballistics is the science of analyzing firearm usage in crimes.

Taken from Wikipedia

Parabolic Velocity

in astronomy, the velocity a body would need to make a parabola about the centre of attraction (also called ESCAPE VELOCITY).

Taken from Dictionary of Science

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The velocity which an object at a given point would require in order to describe a parabola about the center of attraction. This is also the escape velocity since it is the upper limit of velocity on a closed curve. It is obtained by multiplying the velocity of an object moving in a circular orbit by the square root of 2 (approx. 1.414). For example, if the Earth's mean velocity around the Sun of 29.8 km/sec. (18.5 miles/sec.), in a near circular orbit, were increased to 42 km/sec. (26 miles/sec.), the Earth would move to a parabolic path and escape from the solar system.

Taken from The Internet ENCYCLOPEDIA OF SCIENCE

Acceleration

is when the speed at which an object is traveling is further increased. The object travels faster because some force is applied to push or pull the object, making it move more quickly. In physics, when calculations are made concerning acceleration, it is usually represented by the symbol α and is measured in metres per second, per second or metres per second squared (written in mathematical shorthand as ms^-2).

When bodies fall freely under the influence of the force of GRAVITY they all fall at the same rate, that is at a uniform acceleration. Whether the object is a lead weight or a feather they fall at the same rate due to gravity. The reason that in reality the lead weight hits the ground before the feather is due to air resistance holding back the feather. Acceleration due to gravity is approximately 9.8 metres per second per second so when the air resistance is very little, the velocity (speed) of a falling object increases by 9.8 metres per second, per second. On the other hand, an object shot straight upwards with a particular velocity will slow down (decelerate) by the same rate every second until it reaches its greatest height after a particular period of time. When this maximum height is reached, the object that had been shot straight upwards (no horizontal motion whatsoever) will start to fall with an acceleration of 9.8 ms-2.

Taken from Dictionary of Science

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In physics, and more specifically kinematics, acceleration is the change in velocity over time. Because velocity is a vector, it can change in two ways: a change in magnitude and/or a change in direction. In one dimension, i.e. a line, acceleration is the rate at which something speeds up or slows down. However, as a vector quantity, acceleration is also the rate at which direction changes. Acceleration has the dimensions L T⁻². In SI units, acceleration is measured in metres per second squared (m/s²).

In common speech, the term acceleration commonly is used for an increase in speed (the magnitude of velocity); a decrease in speed is called deceleration. In physics, a change in the direction of velocity also is an acceleration: for rotary motion, the change in direction of velocity results in centripetal (toward the center) acceleration; where as the rate of change of speed is a tangential acceleration.

In classical mechanics, for a body with constant mass, the acceleration of the body is proportional to the resultant (total) force acting on it (Newton's second law):

where F is the resultant force acting on the body, m is the mass of the body, and a is its acceleration.

Taken from Wikipedia

Radar

(radio detection and ranging) the use of radio waves to discover the presence and distance of an object. Radar is used in the navigation of aircraft, ships, missiles and satellites.

Taken from Dictionary of Science

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Radar is an object detection system that uses electromagnetic waves to identify the range, altitude, direction, or speed of both moving and fixed objects such as aircraft, ships, motor vehicles, weather formations, and terrain. The term RADAR was coined in 1941 as an acronym for RAdio Detection And Ranging. The term has since entered the English language as a standard word, radar, losing the capitalization. Radar was originally called RDF (Radio Direction Finder, now used as a totally different device) in the United Kingdom, in order to preserve the secrecy of its ranging capability

Taken from Wikipedia

Mach number

the speed of a body expressed as a ratio with the SPEED OF SOUND. Mach I is sonic speed, and thus below I is subsonic and above I is supersonic.

Taken from Dictionary of Science

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Mach number (Ma or M) (generally pronounced /ˈmɑːk/, sometimes /ˈmɑːx/ or /ˈmæk/) is the speed of an object moving through air, or any fluid substance, divided by the speed of sound as it is in that substance. It is commonly used to represent an object's (such as an aircraft or missile) speed, when it is travelling at (or at multiples of) the speed of sound.

where

is the Mach number

is the speed of the source (the object relative to the medium) and

is the speed of sound in the medium

Aberration

is what happens in physics when a lens (or curved mirror) does not produce a true image. It is caused by the light rays from any point on the object being viewed forming an image (focusing) at slightly different positions. In astronomy, aberration refers to the apparent change in position of a star. This is due to the fixed speed of light travelling from the star and the movement of the person looking at the star, because the Earth is moving in its orbit.

Taken from Dictionary of Science