1. GENERAL SCIENCE REVIEWER
THIRD QUARTER 2012-2013
MOTION WAVES
• Before you will be able to describe the • a periodic disturbance that moves away
motion of an object, you must first be from a source and carries energy with it
able to tell exactly where it is • A vibration causes wave motion. When
positioned. Describing exact position you observe a wave, the source is
entails two ideas: describing how far always a vibration.
the object is from the point of PARTS OF A WAVE
referenceand describing its direction Crest- highest point
relative to that point of reference. Trough- lowest point
POINT OF REFERENCE Wave length- distance between 2 waves (trough
• Something to refer to: something to to trough/ crest to crest)
which somebody can refer in order to Wave height- distance from crest to trough
check direction, as a guide or as an aid Amplitude- range from normal position of wave
to communication. to either side
• The object or point from which
movement is determined.
• Movement is relative to an object that
appears stationary.
DISTANCE
• the total length of the path travelled by
the object
• the length of the entire path that the
object travelled
DISPLACEMENT
FREQUENCY
• the distance between the initial position
• is the number of waves that pass a
and final position of the object
particular point every one second
• the shortest distance between the
PERIOD
object’s two positions, like the distance
• the time required for one complete wave
between its point of origin and its point
to pass a given point
of destination, no matter what path it
SPEED/VELOCITY
took to get to that destination
• V = wavelength x frequency
SPEED
LONGITUDINAL WAVES
• Speed is the distance traveled in a given
• occur when the individual particles of
amount of time.
amedium vibrate back and forth in the
• Scalar quantity
direction in which thewaves travel
• Speed= Distance
TRANSVERSE WAVES
Time
• occur when the individual particles or
• 100 km/h
segments of a medium vibrate from side
VELOCITY
to side perpendicular tothe direction in
• Speed with direction
which the waves travel
• Vector quantity
• Velocity = Displacement
Time
• 100 km/h North East
ACCELERATION
• the rate at which the velocity of a body
changes with time
• a = V final – V initial
Time
• If an object does not change its position
at a given time interval,then it is at rest
or its speed is zero or not accelerating.
• If an object covers equal distance at MECHANICAL WAVES
equal intervals of time, then itis • require a medium for wave propagation
moving at constant speed and still not • (medium: rope, coil spring, air, water)
accelerating. ELECTROMAGNETIC WAVES
• If an object covers varying distances at • requireno material medium for their
equal intervals of time, thenit is passage. Thus, they can pass through
moving with changing speed or empty space.
velocity. It means that theobject is • (gamma waves, UV waves, radio waves)
accelerating.
2. SOUND WAVES otherforms or transferred to other
• longitudinal and mechanical waves objects orplaces.
• travels the fastest in solidthan in liquid • Object which has greater mass has
and in air greater heat energy.
• V = 331 + (temperature in air) x 0.6 HEAT TRANSFER
• Reflection = echo • related to change in temperature or
LIGHT WAVES change in the relative hotness or
• Light travels in straight lines coldness of an object.
• Light travels much faster than sound HEAT TRANSFERS IN THREE WAYS:
• We see things because they reflect light • Conduction- higher temperature to
into our eyes lower temperature (spoon gets hot when
• Shadows are formed when light is put in a hot soup)
blocked by an object • Convection- cool air sinks, warm air
• 300, 000, 000 m/s speed of light rises
• travels the fastest in the vacuum • Radiation- particles travel through a
COLOR vacuum
• Light is the combination of all (seven)
colors. ELECTRICITY
• Light can be separated using a prism in • a type of activity arising from the
a process called dispersion. existence of charge
• RED, BLUE and GREEN (primary • The basic unit of charge is that on the
colors) proton or electron.
• The protons charge is called positive
COLOR COMBINATION while the electron's is negative.
• A particle of matter usually has a
charge.
• The charge is positive or negative.
• Two particles with the same charges,
both positive or both negative, repel
or drive away each other, while two
particles with unlike charges are
attracted.
CONDUCTORS
• allow electricity to flow through them
RGB (RED GREEN BLUE) easily. Copper wire is a good example
and makes up our housing and appliance
Blue + Green = Cyan
Blue + Red = Magenta wiring
Red + Green = Yellow INSULATORS
• materials that don't allow electricity to
Blue + Green + Red = White
pass through them easily. Materials such
CMYK (CYAN, MAGENTA, YELLOW, KEY/BLACK) as rubber are good insulators and are
Cyan + Magenta= Blue used around appliance and house wires
to keep the electricity from creating a
Cyan + Yellow = Green
Yellow + Magenta = Red short circuit
THE LAW OF CONSERVATION OF CHARGE
Cyan + Magenta+ Yellow = Black
• Charges cannot be created nor
destroyed, but can betransferred from
HEAT WAVES
one material to another.The total charge
• a form of energy that refers to the
in a system must remain constant.
thermal energy that is ‘in transit’ or in
ELECTROSTATIC LAW
the process of being transferred.
• Like charges repel and unlike charges
• It stops to become heat when the
attract.
transfer stops.
• After the energy is transferred, say to -mct
another object, it may again become
thermal energy or may be transformed
to other forms.
• Any object issaid to possess thermal
energy due to the movement of its STUDY HARD!!!
particles. How isheat related to thermal
energy? GOOD LUCK!!!
• Like any other forms of energy,
thermalenergy can be transformed into