1.

circular motion is a movement of an object along the circumference of a circle or rotation along a circular path. It can be uniform, with constant angular rate of rotation and constant speed, or non-uniform with a changing rate of rotation.

Examples:

a. Playground Merry-go-Rounds

b. Satellites orbiting our Earth

c.

https://en.wikipedia.org/wiki/Circular_motion

http://www.physics.ohio-state.edu/~humanic/p111_lecture10.pdf

2

Angular displacemen - is the angle in radians (degrees, revolutions) through which a point or line has been rotated in a specified sense about a specified axis. When an object rotates about its axis, the motion cannot simply be analyzed as a particle, since in circular motion it undergoes a changing velocity and acceleration at any time (t).

Angular velocity - the rate of change of angular displacement and is a vector quantity (more precisely, apseudovector) which specifies the angular speed (rotational speed) of an object and the axis about which the object is rotating. The direction of the angular velocity vector is perpendicular to the plane of rotation

Angular acceleration – also called rotational acceleration, is a quantitative expression of the change in angular velocity that a spinning object undergoes per unit time. It is a vectorquantity, consisting of a magnitude component and either of two defined directions or senses.Period

Frequency -  number of waves that pass a fixed point in unit time; also the number of cycles or vibrations undergone during one unit of time by a body in periodic motion. A body in periodic motion is said to have undergone one cycle or one vibration after passing through a series of events or positions and returning to its original state.

https://en.wikipedia.org/wiki/Angular_displacement

https://en.wikipedia.org/wiki/Angular_velocity

http://whatis.techtarget.com/definition/angular-acceleration-rotational-acceleration

http://www.britannica.com/science/frequency-physics

4. Centrifugal force (Latin for "center fleeing") describes the tendency of an object following a curved path to fly outwards, away from the center of the curve. It's not really a force; it results from inertia — the tendency of an object to resist any change in its state of rest or motion. 

Centripetal force is a real force that counteracts the centrifugal force and prevents the object from "flying out," keeping it moving instead with a uniform speed along a circular path.

Instances:

A. Roller Coaster,an example of Centripetal force in action

B. A satellite orbiting the planet by applying the centripetal force.

C. The motion in a centrifuge is an example of centrifugal force

D. mud flying off a tire 

http://www.diffen.com/difference/Centrifugal_Force_vs_Centripetal_Force

5.

frequency modulation (FM) is the encoding of information in a carrier wave by varying the instantaneous frequency of the wave. This contrasts with amplitude modulation, in which the amplitude of the carrier wave varies, while the frequency remains constant. In analog frequency modulation, such as FM radio broadcasting of an audio signal representing voice or music, the instantaneous frequency deviation, the difference between the frequency of the carrier and its center frequency, is proportional to the modulating signal.

Amplitude modulation (AM) is a modulation technique used in electronic communication, most commonly for transmitting information via a radio carrier wave. In amplitude modulation, the amplitude (signal strength) of the carrier wave is varied in proportion to the waveform being transmitted. That waveform may, for instance, correspond to the sounds to be reproduced by a loudspeaker, or the light intensity of television pixels. This technique contrasts withfrequency modulation, in which the frequency of the carrier signal is varied, and phase modulation, in which its phase is varied.

https://en.wikipedia.org/wiki/Amplitude_modulation

https://en.wikipedia.org/wiki/Frequency_modulation