Transcript Benchmark review power point

•Remember you can only have one independent
variable in an experiment.(The thing you are
testing and change). The independent variable
goes on the x-axis when graphed.
•All other parts of the experiment must remain
the same (Constants)
•The result you MEASURE is called the
Dependent variable. The dependent variable
goes on the y axis when graphed.
Amusement Park Forces
Physics
8.6a- Demonstrate and calculate how
unbalanced forces change the speed and
direction of an objects motion.
Activities:
Gizmo: Force and Fan Carts
Lab: Car ramps (clay on string, and added
weight to car)
Lab: Newton’s Cart lab: Pennies in film
canister and you burned the string
What is a Force?
FORCE = Any push or pull which causes
something to move or change its speed or
direction
What is a Force?
Forces can be BALANCED or UNBALANCED
Balanced forces are equal in size and
opposite in direction
unbalanced forces are not equal in size
and/or opposite in direction. If the forces on
an object are UNBALANCED, we say a NET
force results.
Amusement Park Forces
Friction is a Resistance
Force
Friction = A force that opposes or slows
down motion
Caused by the physical contact between
moving surfaces
The amount of friction depends upon the
kinds of surfaces and the force pressing
the surfaces together
Changes motion into heat
If you have 30N of force pulling left and another 20N of force pushing left,
what is the total amount of force and in which direction?
50 N to the Left.
What would be the best description of the net
force between a woman and the chair she is
sitting in?
0N – because the forces are
balanced
What is the net force on the box below?
5N right
Luis pushes a toy race car down the floor to the left with 5N of force.
Jonathon then pushes the race car in the same direction with another 6N
of force. Which direction did the race car move and with how much force?
11 N left
What is Friction?
What are some ways athletes uses
friction?
Forces affect Motion:
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They can make objects start moving.
They can make objects move faster.
They can make objects move slower.
They can make objects stop moving.
They can make objects change direction.
They can make objects change shape.
Physics
8.6b- Differentiate between speed, velocity
and acceleration
Activities:
-Motion detector Lab
-Catch the Cheetah graph matching
What is Motion?
Motion: A change in position of an object
compared to a reference point
Motion involves all of the following:
What is Motion?
Speed
The rate of change in position
Speed = distance ÷ time or
Distance
Time
Speed
A ladybug crawls a distance of 50
centimeters in 20 seconds. What is
the ladybug’s average speed?
Speed = distance ÷ time or
Distance
Time
50/20 = 2.5 cm/sec
What is Motion?
Velocity
Speed plus direction
Example: 50 km/hour north
What is Motion?
Acceleration
The rate of change in velocity
Positive acceleration = speeding up
Negative acceleration = slowing down (decelerate)
Interpret The Graph Below:
The graph shows
an object which
is not moving (at
rest).
Interpret The Graph Below:
a
b
The objects are
moving at a constant
velocity- a is moving
faster than b
because it has a
greater slope
Interpret The Graph Below:
an object
moving with
constant
velocity
towards you
Interpret The Graph Below:
Curve line up
shows
acceleration
Interpret The Graph Below:
Curve lines up
show
acceleration –in
Red and
Deceleration in
black
Interpret The Graph Below:
The graph shows
that the objects
velocity does not
change as time
passes.
It shows constant
velocity.
Interpret The Graph Below:
The graph shows
that the objects
velocity is
increasing as time
passes – it is
accelerating.
8.6c-Investigate and describe application of Newton’s Laws of
Motion
Activities:
-Lab Stations- roller coaster, film canister rockets,
crash car with toy doll, and putting golf balls
- Force, mass and acceleration of a BB and marble
-Newton’s Cart Lab-
First Law(Law of Inertia): An object at
rest stays at rest or an object in motion,
stays in motion (in the same direction/at the
same speed) unless acted upon by an
unbalanced force
Inertia
The tendency of an object to resist any
change in its motion
The greater the mass the greater the inertia
The greater the speed the greater the inertia
Examples of Newton’s 1st Law
(do not copy)
a) car suddenly stops and you strain
against the seat belt
b) when riding a horse, the horse
suddenly stops and you fly over its
head
c) the magician pulls the tablecloth out
from under a table full of dishes
d) the difficulty of pushing a dead car
e) lawn bowling on a cut and rolled
lawn verses an uncut lawn
Second law (Law of Force and Acceleration):
The greater the force, the greater the
acceleration
The greater the mass, the greater the force
needed for the same acceleration
Calculated by: F = ma
 (F = force, m = mass, a = acceleration)
Examples of Newton’s 2nd Law of
Force and Acceleration
(do not copy)
a) hitting a baseball, the harder the
hit, the faster the ball goes
b) accelerating or decelerating a
car
c) The positioning of football
players - massive players on the
line with lighter (faster to
accelerate) players in the backfield
d) a loaded versus an unloaded
truck
Third law (Law of
ActionReaction): For
every action force, there
is an equal and opposite
reaction force. (Forces
are always paired)
Examples of Newton’s 3rd
Law
a)rockets leaving earth
b)guns being fired
c) two cars hit head on
d) jumping out of a boat onto
the dock
Examples of Newton’s 3rd Law
Potential Energy (PE)- Energy of
position
Kinetic Energy (KE)- Energy of
motion
Always check the margin titles of
any graph to help you answer
questions.
Moving at a steady
Rate or pace
Time (sec)
Moving at a steady
Rate or pace
Distance
(m)
Speed
(m/s)
Speeding up or
accelerating
Not moving
Time (sec)
Chemistry
8.5a- Describe the structure of atoms,
including the masses, electrical charge
and locations, of protons, and neutrons in
the nucleus and electrons in the electron
cloud.
Activities:
-Building atom models
- Drawing Bohr models and building the
periodic table
Name of
subatomic
particle
proton
electron
neutron
Charge of
Particle
Where it is
found
Size/mass
Positive (+)
inside the
nucleusidentifies
the atom
1 atomic
mass unit
Negative (-)
in electron cloud /
orbiting around
nucleusdetermines
reactivity of
element
Neutral (0)
inside the
nucleus- just
adds
mass/weight
Almost zero
1/1836 amu
(very small!)
1 atomic
mass unit
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8.5b- Identify that protons determine an
elements identity and valence electrons
determine its chemical properties including
reactivity.
Elements in the same group
have similar properties and
reactivity because they have
the same valence. A stable
valence is 8 for all elements
except Hydrogen and Helium.
A stable valence for these
elements is 2.
Group 18 is unreactive
because all elements have a
full valence shell!!
As you move down the group
elements become more reactive
because they have more
electron energy levels. The
electrons are farther away
from the nucleus.
8.5c-interpret the arrangement of the periodic table, including groups
and periods, to explain how properties are used to classify elelments
Chemical Reactions
8.5e- investigate how evidence of chemical
reactions indicate that new substances with
different properties are formed.
Activity: Lab: Evidence of chemical
reactions.
Chemical Property- ability of an element or
compound to react with another substance.
Key words: oxidation, reactivity, flammability
Clues that indicate a chemical reaction:
1.The production of a gas.
Evidence: bubbles, odor
2.A Change in temperature (can
be an increase or decrease)
3.Production of a precipitate(makes a solid, often looks like a
powder)
4.A color change- Clear + Clear
= different color
8.5d- Recognize that chemical formulas are used to identify substances
and determine the number of atoms of each element in chemical
formulas containing subscripts.
What elements are in this compound?
Copper, Sulfur, Oxygen
How many atoms of each?
Copper=2, Sulfur=2, Oxygen=8
Total number of atoms
12
Chemistry
8.5f- Recognize whether a chemical
equation containing coefficients is
balanced or not and how that relates to the
law of conservation of mass
Activities:
-Build me balance me
-Balancing equations worksheets
The Law of Conservation of
Mass
• States that matter can neither be created nor destroyed.
– Atoms do not disappear in a chemical reaction! –
they rearrange themselves into the new substances
(products).
• Equations have to be balanced with coefficients
(representing the # of molecules) in order to support this
law.
– The # of atoms of each element must be the same
on both sides of the equation!
– Multiply the coefficient by the subscript to calculate
number of atoms.
Photosynthesis Equation Example:
H20 + C02
C6H1206 + 02
unbalanced
6H20 + 6C02
C6H1206 + 602
balanced
H= 12
O=12 + 6 = 18
C=6
C=6
H= 12
O=6 + 12 = 18
Astronomy
8.8a- Describe components of the universe including stars, nebulae, and
galaxies, and use models such as the Hertzsprung-Russell diagram for
classification.
8.8b. Recognize that the Sun is a medium sized star near the edge of a
disc-shaped galaxy of stars and that the Sun is many thousands of times
closer to Earth than any other star.
8.8c. Explore how different wavelengths of the electro-magnetic spectrum
such as light and radio waves are used to gain information about
distances and properties of components in the universe.
8.8d- Model and describe how light years are used to measure distances
and sizes in the universe.
Astronomy
Notes
Image From: http://www.astronomy-pictures.net/spiral_galaxy.jpg;
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Stars
• An object made of gas that gives off energy
– mainly hydrogen
– helium
The Sun
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•
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•
medium in size & life span compared to other stars
primary energy source for all processes on Earth
much closer to Earth than any other star!
about 4 ½ billion years old
H-R Diagram: Shows the relationship between
color, temperature, magnitude & size of stars.
Magnitude
• Color = temperature
• Magnitude = how bright
• Our Sun is a main sequence star.
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Black Dwarf
Nebula
1. Large
cloud of
gas & dust
where
stars form.
2. Gravity pulls
4. Outer layers
5. Collapses
material into a
come off
sphere that
to just its
3. Expands
becomes
core
dense, hot
Explodes!
& ignites.
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Galaxy
• A large grouping of stars in space.
• 3 types
1. Spiral – bulge in center & distinctive spiral arms
•
•
Example: Our galaxy, The Milky Way
Our solar system is located within an arm
2. Elliptical – spherical or elongated
3. Irregular
1
2
3
Light Year
A measure of how long it takes light to
travel through space in one year.
Image From: http://uniqhorns.com/images/milkyway.gif;
Definition: www.thefreedictionary.com
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Electromagnetic Spectrum
The range of all the waves that can travel
through matter as well as empty space.
R
O
Y
G
B
I
V
Scientists use different
portions of the spectrum to
learn about the universe.
Ex: light waves can tell us
what elements stars are
made & if they are moving
away or towards other
objects.
Image From: http://www.lcse.umn.edu/specs/labs/images/spectrum.gif
Definition: www.thefreedictionary.com
Space Cycle Notes
Created by Harris Middle School
8.7b- demonstrate and predict the
sequence of events in the lunar cycle
8.7c- Relate the position of the moon
and Sun to their effect on ocean tides
8.7a- Model and illustrate how the tilted
Earth rotates on its axis, causing day
and night and revolves around the Sun
causing changes in the seasons.
Moon
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• A natural satellite of a planet.
• The outer planets have many of them!
Image From: http://sos.noaa.gov/images/Solar_System/moon.jpg;
Definition: www.thefreedictionary.com
Lunar
Cycle
Full moon: all of surface facing Earth is
illuminated (= lit) by the Sun
New moon: moon is between Earth & Sun, so lit
portion is facing away from Earth
Waxing moon: lit portion “growing”
Waning moon: lit portion “decreasing”
Gibbous moon: larger than ½
Crescent moon: smaller than ½
Tides
Tide = daily rise & fall in ocean water level
• high and low tides occur twice daily
• high tides are caused by the gravitational pull of the
moon & sun, causing the ocean water to “bulge” away
from the Earth
• the moon has a greater impact because it is closer
High tide occurs on the side facing the moon, but it
also occurs on the opposite side. This is because the
moon is also pulling the Earth away from the water on the
other side.
Low Tide
Tidal bulge
High Tide
High Tide
Low Tide
Gravitational pull
of the moon
moon and sun
pull together =
largest tides
moon and sun
pull against
each other =
weakest tides
Rotation vs. Revolution
Rotation:
• spin of object on its axis
• rotates counter-clockwise = west to east
= why sun appears to rise in the east and set in the west
• for Earth = 24 hrs. =1 day
• responsible for day vs. night
Revolution:
• also called an orbit
• path of one object around another
• Earth around sun ≈ 365 days = 1 year
• moon around Earth ≈ 1 month
The Earth is tilted on its axis by 23.5.°
As a result, the hemisphere that is tilted toward the sun
receives more direct sunlight = more heat.
• causes longer daylight hours
• hotter temperatures = summer!
The hemisphere tilted away from the sun experiences
winter.
The TILT is
the reason
for seasons!
For the Northern
Hemisphere!
= least daylight hours
= most daylight hours
= Equal hours of day and night
Weather & Climate
Unit Notes
8.10a- recognize that the Sun provides the
energy that drives convection within the
atmosphere and oceans, producing winds and
ocean currents
8.10b- identify how global patterns of
atmospheric movement influence local
weather using weather maps that show high
and low pressures and fronts
8.10c- identify the role of the oceans in the
formation of weather systems such as
hurricanes.
Radiant Energy = from the Sun
• Radiant energy drives changes in
weather & creates different climates.
– Weather changes from day to day.
– Climate = a region’s general pattern of
weather over a long period of time.
• The equator receives the most direct
angle of sunlight, creating the warmest
climates.
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Heating differences
causes there to be
different air masses.
cool air (or water) is
more dense than warm,
so it sinks, creating
currents by convection
sun heats land
and oceans by
radiation
land/ocean
heats the air
above it by
conduction
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Air movements create weather changes.
Air mass = A body of air that has similar pressure,
temperature, & humidity.
•Different air mass pressures cause wind.
• Air moves from high to low pressure areas.
-Generally blow from poles toward equator
-Weather often changes when air pressure changes
-A front is where two air masses meet or collide
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Warm air rises, decreasing
the air pressure.
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Land-Ocean Interactions
Land heats up faster than water (= the ocean).
– The air over the land will also heat quickly.
– Warm air rises, starting a convection current.
– This brings moist ocean air inland.
• Ocean air holds a lot of water vapor.
• Warm air can also hold more water vapor.
– When air cools, it may no longer be able to
hold on to all of the water vapor, forming
clouds & precipitation.
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Vocab !
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• Oceans can also influence weather in
extreme ways, such as in the formation of
hurricanes.
= A low pressure tropical storm that forms over ocean
water.
• Oceans impact climate because they heat
and cool slowly (=good insulator!).
– Land near the ocean is often warmer in winter and
cooler in summer, meaning inland climates differ
from those near the ocean at the same latitude.
• Oceans also impact climate via currents…
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Current – movement of water in the ocean
• Surface currents are affected by  Winds
 Continental deflections
 Coriolis Effect – following the
curve of the Earth as it rotates
• Deep ocean currents are affected by  Temperature differences (density)
 Salinity differences (density)
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Movement of currents is constant and
creates a “global conveyor belt” that
transfers heat from one part of the
Earth to another via water.
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Ocean currents can bring in air of a different
temperature that makes one area on Earth
warmer than another at the same latitude
– Example: Gulf Stream brings warm air into
England, making it warmer than Nova Scotia,
Canada at the same latitude.
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L= Low pressure, cloudy and often rainy conditions
H= High pressure, clear and pleasant skies. High means dry…
When fronts move thru of extreme temperatures you often get
thunderstorms.
Cold fronts move from poles toward equator- have triangle flags (think
icicles)
Warm fronts move from equator toward poles- have half circle flags (think
rising sun)