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7/29/2019 PS PSSA Prep Physics Review
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PSSA Science Prep - Physics
TIME INTERVALS FOR ERUPTIONSOF OLD FAITHFUL GEYSER
Duration of
Eruption
Time to Next
Eruption
2.0 min 57 min
3.0 min 71 min
4.0 min 82 min
5.0 min 95 min
A tourist views an eruption thatlasts 4.5 minutes. Based on the
data in the table, about howlong will the tourist most likelyhave to wait to see the nexteruption?
A. 82 minutesB. 88 minutes
C. 95 minutes
D. 102 minutes
Answer on Next Slide.
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PSSA Science Prep - Physics
TIME INTERVALS FOR ERUPTIONSOF OLD FAITHFUL GEYSER
Duration of
Eruption
Time to Next
Eruption
2.0 min 57 min
3.0 min 71 min
4.0 min 82 min
5.0 min 95 min
A tourist views an eruption thatlasts 4.5 minutes. Based on the
data in the table, about howlong will the tourist most likelyhave to wait to see the nexteruption?
A. 82 minutesB. 88 minutesC. 95 minutes
D. 102 minutes
Answer on Next Slide.
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Objectives:Eligible Content for Physics, Grade 8
Distinguish among forms of energy(e.g., electrical, mechanical, chemical,light, sound, nuclear) and sources of energy(i.e., renewable and nonrenewable energy) .
Describe the Sun as the major source of energythat impacts the environment.
Compare the time span of renewability for fossil
fuels and the time span of renewability foralternative fuels..
S8.C.2.1.1
Explain how energy is transferred from one place toanother through convection, conduction, or radiation.
S8.C.2.1.2
S8.C.2.2.2
S8.C.2.1.3
S8.C.2.2.1
Describe how one form of energy (e.g., electrical,mechanical, chemical, light, sound, nuclear) can be
converted into a different form of energy.
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Describe the waste (i.e., kind and quantity) derivedfrom the use of renewable and nonrenewableresources and their potential impact on theenvironment.
Describe forces acting on objects (e.g., friction,gravity, balanced versus unbalanced).
Objectives:Eligible Content for Physics, Grade 8
Explain that mechanical advantage helps todo work (physics) by either changing a force orchanging the direction of the applied force(e.g., simple machines, hydraulic systems).
S.8.C.2.2.3
S.8.C.3.1.1
S.8.C.3.1.2
S.8.C.3.1.3
Distinguish between kinetic and potential energy.
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Chemical a form of potential energy stored inchemical bonds
Electrical - the energy associated with electric charges
Light (Radiant): a form of electromagnetic energy, thevibration of electrically charged particles the ONLY form ofenergy that can travel through the vacuum of space
Mechanical the energy that an object has due to itsposition or motion
Nuclear- the energy that can be released by changes
in the nucleus of an atom Sound- energy produced when matter vibrates
Thermal- the energy of an object due to the randommotion of its particles
Forms of EnergyUnit 6 Lesson 1
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Potential: Energy that is stored in an objectdue to its position relative to something else(the reference level) 2 forms
1. Gravitational (GPE) PE due to height above ground
2. Elastic (EPE)
PE due to stretching/deforming Kinetic: Energy of motiondepends on mass AND
speed (more of either means more KE)
Law of Conservation of Energy energy can
be transformed from one type to another Example 1 Yo-Yo: PEKEPEKE..
Example 2 Flashlight:
Battery converts chemical to electrical energy
Bulb converts electrical to light energy
Forms of Mechanical EnergyUnit 6 Lessons 3 & 4
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An object is lifted into the air anddropped. Which statement bestdescribes the objects energy as it fallsthrough the air from the stationary
position at height X?
A. At height X, the energy is potential, whichchanges to kinetic as the object falls.
B. At height X, the energy is kinetic, which changesto potential as the object falls.
C. At height X, the energy is potential and kinetic,and the object loses potential energy as it falls.
D. At height X, the energy is potential and kinetic,and the object loses kinetic energy as it falls.
Sample PSSA Question 1Kinetic vs. Potential Energy (C.3.1.2)
Answer on Next Slide.
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An object is lifted into the air anddropped. Which statement bestdescribes the objects energy as it fallsthrough the air from the stationary
position at height X?
A. At height X, the energy is potential, whichchanges to kinetic as the object falls.
B. At height X, the energy is kinetic, which changesto potential as the object falls.
C. At height X, the energy is potential and kinetic,and the object loses potential energy as it falls.
D. At height X, the energy is potential and kinetic,and the object loses kinetic energy as it falls.
Sample PSSA Question 1Kinetic vs. Potential Energy (C.3.1.2)
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Sample PSSA Question 2Science Scenario: Energy Transformation (C.2.1.3)
Students made the device shown at left for testingthe effects of different electromagnetic fields onsubstances. The testing device has three batteries,three coils of insulated copper wire, one iron rod,three adjustable selector switches, and one on/offswitch with a power indicator light.
Which sequence correctly shows the energyconversions that allow the testing device to
attract a metal weight with magnetic properties?
A. battery (chemical to heat) wire coil (heat to
magnetic) metal weight (magnetic to frictional)
B.
battery (chemical to electrical)
wire coil (electricalto magnetic)metal weight (magnetic to mechanical)
C. battery (electrical to magnetic) wire coil (magnetic to
heat) metal weight (heat to mechanical)
D. battery (electrical to mechanical) wire coil
(mechanical to magnetic)metal weight (magnetic to
gravitational)Answer on Next Slide.
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Sample PSSA Question 2Science Scenario: Energy Transformation (C.2.1.3)
Students made the device shown at left for testing theeffects of different electromagnetic fields onsubstances. The testing device has three batteries, threecoils of insulated copper wire, one iron rod, threeadjustable selector switches, and one on/off switchwith a power indicator light.
Which sequence correctly shows the energyconversions that allow the testing device to attract a
metal weight with magnetic properties?
A. battery (chemical to heat) wire coil (heat to magnetic)
metal weight (magnetic to frictional)
B.
battery (chemical to electrical)
wire coil (electrical tomagnetic) metal weight (magnetic to mechanical)
C. battery (electrical to magnetic) wire coil (magnetic to
heat) metal weight (heat to mechanical)
D. battery (electrical to mechanical) wire coil (mechanical
to magnetic)metal weight (magnetic to gravitational)
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Renewable: an energy source thatcan be replaced in our lifetime.
Examples: Sunlight, wind, moving water,
wood, biomass (burning garbage)
NonRenewable: an energy sourcethat cannot be replaced in our lifetime.
Examples: Oil, natural gas, coal, uranium
(nuclear fuel) geothermal
Environmental Impact:
a) WHICH type (above) do you think pollutes more?
b)
What OTHER environmental consequences are there?
Energy Sources & Waste
.
Unit 6 Lesson 1
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Which energy source can be described as having the
greatest impact on Earths living environments?
A. moving air
B. moving water
C. the Sun
D. geothermal
Sample PSSA Question 3Energy Impact on Environment (C.2.2.1)
Answer on Next Slide.
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Which energy source can be described as having the
greatest impact on Earths living environments?
A. moving air
B. moving water
C. the Sun
D. geothermal
Sample PSSA Question 3Energy Impact on Environment (C.2.2.1)
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Which of the following would most likely result
from replacing conventional cars with solar-
powered cars?
A. Increases in acid precipitation rates
B. Increased use of nonrenewable resources
C. Reduced need for other forms of transportation
D. Smaller amounts of greenhouse gases in the
atmosphere
Sample PSSA Question 4Energy Sources & Waste (C.2.2.3)
Answer on Next Slide.
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Which of the following would most likely result
from replacing conventional cars with solar-
powered cars?
A. Increases in acid precipitation rates
B. Increased use of nonrenewable resources
C. Reduced need for other forms of transportation
D. Smaller amounts of greenhouse gases in the
atmosphere
Sample PSSA Question 4Energy Sources & Waste (C.2.2.3)
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Conductionthe movement ofthermal energy bybodies or fluidsthat are in contact
Convectionthe transfer ofheat by thecirculation ormovement of the
heated parts of aliquid or gas
Radiationthermal energytransmitted aswaves
Heat AND Light canmove in this way
ONLY form of
energy that can
move through a
vacuum (space)
How Energy MovesUnit 6 Lesson 11
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In the Earth's mantle, heat is transferred in large
convection currents. Within these currents,
A. hotter and cooler rock sink but do not rise.
B. cooler and hotter rock rise but do not sink.
C. hotter rock rises and cooler rock sinks.
D. cooler rock rises and hotter rock sinks
Sample PSSA Question 5Energy Transfer (C.2.1.2)
Answer on Next Slide.
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In the Earth's mantle, heat is transferred in large
convection currents. Within these currents,
A. hotter and cooler rock sink but do not rise.
B. cooler and hotter rock rise but do not sink.
C. hotter rock rises and cooler rock sinks.
D. cooler rock rises and hotter rock sinks
Sample PSSA Question 5Energy Transfer (C.2.1.2)
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Forcea push or a pull that can cause an object tomove, stop moving, change speed or direction
Frictiona force that resists motion between twoobjects that are in contact converts kinetic energyinto heat
Gravity- a universal force that every mass exerts onevery other mass
Weight the force of gravity on an object depends
on location Mass - the amount of matter in an object does
NOT depend on location
Bouyant Force the upward force on an objectwhich is immersed in a fluid
Forces on ObjectsUnit 4 Lesson 1,2.9,10
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BALANCED MOTION UNCHANGED
Unbalanced forces haveunequal magnitudes and/ordirections.
Unbalanced forces result in netforces.
Net forces change an object'svelocity by changing the object'sspeed and/or direction
The change in motion will be in
the direction of the net force (2nd
Law)
UNBALANCED ACCELERATION
Net ForcesUnit 4 Lesson 1
Book exerts a gravitational force
(weight force) downward on the
table Table exerts an equal and
opposite force up on the book
(Newton's 3rd Law)
Since these forces are balanced,
the book rests on the table; itdoes not move.
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Sample PSSA Science Scenario
Students made the device shown at left fortesting the effects of differentelectromagnetic fields on substances.
The testing device has three batteries, threecoils of insulated copper wire, one ironrod, three adjustable selector switches, andone on/off switch with a power indicatorlight.
Six metal weights are available for thetests; each weight has the same volume andmass.
The strength of the electromagnet ismeasured by counting the number of metalweights that can be suspended from the rod
like a chain. A description of the functionsofthe devices switches isbelow
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Sample PSSA Question 6Science Scenario: Forces on Objects(A.2.1.6)
Students attempted to use the device and the weights in an
investigation. None of the metal weights were attracted to the
electromagnet when they were placed near it. The students made
sure that the power indicator light was on, then they tried every
switch combination. Which system modification and test are
necessary to solve the design flaw in the experimental setup?
A. Use copper metal weights and test the batteries.
B. Use a copper rod and test the batteries.
C. Use smaller metal weights and test the original weights and
the smaller weights with a bar magnet.
D. Use a larger iron rod and test the original metalAnswer on Next Slide.
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Sample PSSA Question 6Science Scenario: Forces on Objects(A.2.1.6)
Students attempted to use the device and the weights in an
investigation. None of the metal weights were attracted to the
electromagnet when they were placed near it. The students made
sure that the power indicator light was on, then they tried every
switch combination. Which system modification and test are
necessary to solve the design flaw in the experimental setup?
A. Use copper metal weights and test the batteries.
B. Use a copper rod and test the batteries.
C. Use smaller metal weights and test the original weights
and the smaller weights with a bar magnet.
D. Use a larger iron rod and test the original metal
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Sample PSSA Question 7Science Scenario: Forces on Objects(C.3.1.1)
Which statement correctly describes the forces acting on the
metal weights when the system design prevented them from
being attracted to the electromagnet?
A. The balanced magnetic and gravitational forces wereinsufficient to overcome the inertia of the metal weight.
B. The balanced frictional and gravitational forces were
insufficient to overcome the momentum of the metal weight.
C. The unbalanced frictional and gravitational forces were
insufficient to overcome the inertia of the metal weight.
D. The unbalanced magnetic and gravitational forces were
insufficient to overcome the momentum of the metal weight.
Answer on Next Slide.
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Sample PSSA Question 7Science Scenario: Forces on Objects(C.3.1.1)
Which statement correctly describes the forces acting on the
metal weights when the system design prevented them from
being attracted to the electromagnet?
A. The balanced magnetic and gravitational forces wereinsufficient to overcome the inertia of the metal weight.
B. The balanced frictional and gravitational forces were
insufficient to overcome the momentum of the metal weight.
C. The unbalanced frictional and gravitational forces were
insufficient to overcome the inertia of the metal weight.
D. The unbalanced magnetic and gravitational forces were
insufficient to overcome the momentum of the metal weight.
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Six Types:* Lever * Pulley * Wedge
* Inclined Plane * Wheel&Axle * Screw
Simple Machines:
Make work easier when a single force is applied
Do NOT multiply workonly multiply or change the direction
of the input force (ex: Pulley converts downward input force
into upward output force)
Work = force x distance
If the output force is multiplied/increases, then the output
distance the load moves must ________ to keep the total
work done the SAME.
Simple MachinesUnit 6 Lesson 8
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Sample PSSA Open-Ended ItemEnergy Transformation (C.3.1.3)
A worker needs to move a box of heavyequipment from the ground to a platform 2meters high. Rather than lift the box, theworker can use one of two ramps. Ramp X is7 meters long and ramp Y is 3 meters long.
Part A: Why would a worker use a ramp rather than lift the box?________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
Part B: Choose either ramp X (7 meters long) or ramp Y (3 meters long) and explainthe benefits of using that ramp instead of the other ramp.
________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
Answer on Next Slide.
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Sample PSSA Open-Ended ItemEnergy Transformation (C.3.1.3)
A worker needs to move a box of heavyequipment from the ground to a platform 2meters high. Rather than lift the box, theworker can use one of two ramps. Ramp X is7 meters long and ramp Y is 3 meters long.
Part A: Why would a worker use a ramp rather than lift the box?A ramp requires less force to move the box. Therefore it is easier on the workerand easier to move.
Part B: Choose either ramp X (7 meters long) or ramp Y (3 meters long) andexplain the benefits of using that ramp instead of the other ramp.Ramp X would be best because it requires less force to move the box up it. Ifyou increase the distance of the ramp, you decrease the amount of forceneeded to move it.
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An engineer needs to design a bridge that can withstand
drastic changes in temperature. An understanding of
which of the following concepts would most likely help
the engineer design the bridge?
A. The universal law of gravitation
B. The conservation of momentum
C. The theories of chemical bonding
D. The process of thermal expansion
Exit Ticket
Answer on Next Slide.
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An engineer needs to design a bridge that can withstand
drastic changes in temperature. An understanding of
which of the following concepts would most likely help
the engineer design the bridge?
A. The universal law of gravitation
B. The conservation of momentum
C. The theories of chemical bonding
D. The process of thermal expansion
Exit Ticket