Science 4th grade, UNIT 6 "Light and Sound"
Science 4th grade
UNIT 6
LIGHT and SOUND
J. Cesar Brazo Mur
El Tomillar, Attendis
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Science 4th grade, UNIT 6 "Light and Sound"
ENERGY is the ability to do work They are some common forms of energy
LIGHT
HEAT SOUND
Most energy comes from the SUN
We use energy in everything we do When you travel At home... When you study or run
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Science 4th grade, UNIT 6 "Light and Sound"
We can transform energy from one form to another
Cars transform Windmills transform energy from the wind
energy from petroleum into motion
into electricity Our body transforms nutrients from food into energy to move and do diary activities
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Science 4th grade, UNIT 6 "Light and Sound"
Sources of energy can be classified into... RENEWABLES Come from natural
NON-RENEWABLES
Come from resources that
resources that the
the Earth can't replace,
Earth can replace
so they are limited
Yes!
No! Sun, wind, water, biomass... El Tomillar, Attendis
Does this energy pollute?
Petroleum, gas, coal... 4
Science 4th grade, UNIT 6 "Light and Sound"
TYPES of energy Solar
Comes from the
Chemical Comes from
rays of the Sun
chemical reactions
Mechanical Comes from
Thermal Comes from the motion of small particles
Electrical From electrons in motion
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objects in motion
Electrons are parts of an ATOM (the smallest part of matter)
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Science 4th grade, UNIT 6 "Light and Sound"
LIGHT is a type of energy that can be seen by the human eye Light is a type of ELECTROMAGNETIC RADIATION
WHITE LIGHT
PRISM
is what human eye sees, but light is really a
SPECTRUM
mixture of seven colors When white light passes through a PRISM, it divides into seven colors called SPECTRUM
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Science 4th grade, UNIT 6 "Light and Sound"
PROPERTIES of light
REFLECTION Rays of light reflect in the same direction when they hit a smooth and flat surface But, when rays of light reflect on a rough surface, they reflect in different directions El Tomillar, Attendis
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Science 4th grade, UNIT 6 "Light and Sound"
PROPERTIES of light
REFRACTION When light passes through materials of different densities, the rays of light curve Glass and water have different densities. The eye sees two images
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Science 4th grade, UNIT 6 "Light and Sound"
INSTRUMENTS that control and detect light telescopes
cameras magnifying glasses
binoculars
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microscopes
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Science 4th grade, UNIT 6 "Light and Sound"
SOUND is a form of energy that is produced when matter vibrates. When we throw a stone into the water, it produces waves... AIR
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Sounds make air vibrate in waves that reach our ears 10
Science 4th grade, UNIT 6 "Light and Sound"
SOUND travel through solids, liquids and gases Kinds of sounds
Characteristics
Loud and quiet
INTENSITY
High and low Noises
PITCH DURATION Short / Long
TIMBRE We can distinguish different sounds El Tomillar, Attendis
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Science 4th grade, UNIT 6 "Light and Sound"
CHECKPOINT What must I know after studying? - Definition of 'energy' - Origin of most of the energy - Energy can be transformed - Name and origin of the different kinds of energy - Definition and sources of 'light' - Concepts of 'white light' and 'spectrum' - Properties of light: why do 'reflection' and 'refraction' occur? - Some examples of instruments that we use to detect/control light - Sound: definition, how it moves and kinds of sounds - Name and definition of the characteristics of sound El Tomillar, Attendis
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