Transcript Sensing and Using Energy

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Heat energy has to do
with the internal
motion of particles of
matter
The greater the
motion of the particles
the more heat that is
involved.
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Solar Energy comes
from the sun.
Solar Energy is also
referred to as Light
Energy.
It is the reactant
energy in
photosynthesis.
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Mechanical Energy is
the energy of motion.
In our bodies during
respiration we
convert chemical
energy which is
stored in foods into
mechanical energy so
we can move.
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Chemical Energy is
stored in foods.
Chemical Energy is
also released when a
chemical reaction
takes place.
For example when a
firework explodes you
have chemical energy
being converted into
light energy.
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Is the movement of
electrical charges.
Items that needs
plugged in like a lamp
convert electrical
energy into light
energy.
Batteries in a small car
can convert electrical
energy into
mechanical energy.
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Energy that is stored
and held in readiness is
called Potential Energy.
This type of energy has
the potential to do
work.
The energy of motion is
called Kinetic Energy.
The word kinetic comes
from the Greek word
“kinetos” which means
“moving.”
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Potential Energy and
Kinetic Energy are
cyclically. They are types of
mechanical energy.
Think about it when you
stretch a rubber band, you
give it elastic potential
energy. If you let it go, the
rubber band flies across the
room.
When the rubber band is
moving, it has kinetic
energy. The potential
energy of the stretched
rubber band is converted to
the kinetic energy of the
moving rubber band
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Think about when
you bounce a ball.
When does it have the
most kinetic energy?
When does it have the
most potential
energy?
When would it have
equal amounts of
potential and kinetic
energy?
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A continuous
conversion between
kinetic and potential
energy takes place in a
pendulum.
As the pendulum
swings outward and
slows down it has more
potential energy.
As the pendulum goes
back towards the
middle it gains kinetic
energy.
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At which point on the
pendulum’s swing is
the kinetic energy the
greatest?
At which point on the
pendulum’s swing is
the potential energy
the greatest?
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As water flows through
a dam it can be used to
create electrical energy.
The electrical energy is
formed from the water's
stored gravitational
potential energy.
Why do you think it is
called
GRAVITATIONAL
POTENTIAL
ENERGY?
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A change from one
form of energy to
another is known as
energy conversion.
Energy is neither
created nor destroyed
but only changes form.
Most forms of energy
can converted into other
forms.
A toaster for example
converts electrical
energy into thermal
energy.
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Your body converts
chemical energy in the
food you eat to the
mechanical energy you
need to move your
muscles.
Chemical energy in
food is also converted to
the thermal energy your
body uses to maintain
it’s temperature.
This is known as
cellular respiration.
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Often a series of energy
conversions is needed to
do a task.
Strike a match, for
example, and the
mechanical energy used to
scratch the match is
converted to thermal
energy.
The thermal energy
causes the match to
release stored chemical
energy, which is
converted to thermal
energy.
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Photosynthesis
converts solar energy
into chemical energy
which can be stored
by the plant as food.
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In some animals, the organ
used to detect light is the
eye. Although most large
animals (humans, fish,
birds, reptiles) have similar
eyes, not all eyes are the
same.
Some eyes are very
complex, while others are
simple in their function.
With our human eyes, we
can see a variety of colors,
shades, and sharp details of
shapes by collecting the
light reflected off of objects.
Detecting Light Energy
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So let’s say one weekend as
a class we decide to go
hiking.
During our hike we find a
large cave with many
caverns.
As we travel further into the
cavern we decide to turn
out our light and it is
completely dark.
How long will it take for
our eyes to get use to the
darkness?
Our eyes would never get
used to complete darkness.
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Life as seen through the
eyes of an insect would look
very different. Insect eyes
come in two varieties–
simple and complex.
Simple insect eyes, called
ocelli, detect little detail but
can tell different shades of
light and dark.
Compound eyes are more
complex. These organs
function similarly to many
human eyes bundled
together and working as
one.
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Some critters have eyes
that swivel on short stalks
which help them to see in
all directions with out
turning their heads.
Have you ever tried to
swat a fly? They have
compound eyes that help
them see behind them.
They see behind them but
can't detect shapes very
well. So next time when
you sneak up on a fly,
pretend to being doing
something else.
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Plants can also detect light.
In fact, if they couldn’t, we
could not exist, as we know
it.
Special organs in plants,
called chloroplasts, collect
light energy and use it to
convert carbon dioxide and
water into sugar for us.
There are special
photoreceptors in plants
called cryptochromes and
phytochromes. These
receptors release hormones
called auxins which break
down part of the cell wall so
that the plant is not as rigid
so it can bend towards light.
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'Phototropism' is
directional growth in
which the direction of
growth is determined
by the direction of the
light source.
In other words, it is
the growth and
response to a light
stimulus.
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Even though we can feel
many types of vibrations
with our hands, feet or
other body parts, we
understand sounds by
using our ears.
Human ears, and the ears
of other large animals, are
generally made of an air
chamber covered by a thin
piece of skin-like material
(your eardrum).
Animals Detecting Sounds
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Insect ears, like
human ears collect
and transform sound
vibrations.
But, insects ears are
called tympanic
organs. Any idea why
they have this name?
It is because the
membrane vibrates
like a drum.
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Fish have what is called a
lateral line system to help
detect sound vibrations in
water. This helps them
detect when predators
and other objects are near.
The lateral line looks like
dashed or dotted lines on
the sides and around the
head of fish, reptiles and
amphibian
This system also helps
these animals sense
movement of water past
their bodies, and the
temperature of the water.
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Have you ever burned
your hand on the stove?
How does your brain
actually know that your
hand is getting warm?
We, like other animals,
have certain nerve
endings that are
sensitive to heat.
These are often called
thermoreceptors.
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For some animals,
such as some
amphibians, fish, and
reptiles, these
receptors are part of
the lateral line system.
Insects also have
thermoreceptors
located on all sorts of
different body parts.
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A seismograph
records the ground
movements caused by
seismic waves as they
move through the
Earth.
Electronic
seismographs convert
ground movements
into a signal that can
be recorded and
printed.
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In some people the
eyeball is slightly too
long or too short, so the
image on the retina is
slightly out of focus.
Fortunately, wearing
glasses or contact lenses
can usually correct this
type of vision problem.
By wearing these
products it helps focus
light properly on the
eyes.
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Telescopes use lenses or
mirrors to collect and
focus light from distant
objects.
The most common use
of telescopes is to collect
and use light from
space.
This allows astronomers
to see objects they could
not see with their eyes
alone.
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Hearing loss is
generally due to injury,
infection, or aging.
Some types of hearing
loss can be helped with
hearing aids. Hearing
aids are amplifiers.
Some are so tiny that
they can fit invisibly in
the ear. Others are
made specifically for a
person’s hearing loss
and amplify specific
frequencies.
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A car toy that is
powered by batteries
would be an example
of the conversion of
chemical energy to:
A. Heat Energy
B. Mechanical Energy
C. Nuclear Energy
D. Sound Energy
Answer: B
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Which position has the least kinetic energy?
Position 1 and 3
Which position has the most kinetic energy?
Position 2 and 4
Which position has the least potential energy?
Position 2 and 4
Which position has the most potential energy?
Position 1 and 3
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What energy conversion
takes place during
cellular respiration?
1. Heat Energy to
Mechanical Energy
2. Heat Energy to
Chemical Energy
3. Chemical Energy to
Light Energy
4. Chemical Energy to
Mechanical Energy
Answer: 4
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What energy conversion
takes place in
photosynthesis?
1. Heat Energy to
Chemical Energy
2. Light Energy to Heat
Energy
3. Light Energy to
Chemical Energy
4. Mechanical Energy
to Chemical Energy
Answer: 3
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Identify the energy
change that takes place
as a candle burns.
1. Mechanical to
Electrical Energy
2. Chemical to Heat
Energy
3. Mechanical to Heat
Energy
4. Chemical to
Mechanical Energy
Answer: 2
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Which of these is an
example of chemical
energy being converted
to electrical energy?
A. 9 Volt Battery in a
Smoke Alarm
B. Sunlight Used by
Plants in Photosynthesis
C. A Windmill
generating Electricity
D. A Blender Grinding
up strawberries.
Answer: A
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The burning of
vaporized gas in the
cylinder of an
automobile engine
pushes the pistons. This
is an example of an
energy conversion from
chemical to:
A. Electrical Energy
B. Heat Energy
C. Mechanical Energy
D. Nuclear Energy
Answer: C
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Which of these is an
example of electrical
energy being converted
to mechanical energy?
A. Flashlight
B. Sunlight used by
Photosynthesis
C. Lightning Striking
the Ground
D. Fan
Answer: D
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Identify the energy
change that takes place
in a food blender.
1. Mechanical to
Electrical Energy
2. Electric to
Mechanical Energy
3. Electric to Heat
Energy
4. Chemical to Heat
Energy
Answer: 2