home work for science

1General Science 1B
Credit 2
Rev. 5/5/21
NAME:_________________________
CREDIT 2B: FORCE FIELDS AND ORBITS
Learning Goal for this Credit
Communicate scientific information clearly, thoroughly and accurately.
Lesson
Title
INTRODUCTION
2.1
Gravity
2.2
Orbit
2.3
Magnetism
Assignments

 Connect to Prior Knowledge
 Exploration Activity
 Reading and Questions
 Videos (optional)
 Gravitational Force Simulation
 Review Questions
 Newton’s Thought Experiment
 Exploration Activity
 Reading and Questions
 Videos (optional)
 Gravity and Orbit Simulation
 Review Questions
 Connect to Prior Knowledge
 Exploration Activity
 Reading and Questions
 Videos (optional)
 Compasses and Magnetic Fields
 Review Questions
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PERFORMANCE TASK
QUIZ
Student Support Icons
Title
Icon
Description
Review
Activity
This provides the students with a reminder that they need to answer questions.
Technology
Guides students through the tasks and assignments that require the use of
technology and manipulatives.
Reading
This icon lets the students know they will be completing a reading activity.
Credit Materials
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Materials
Pen/Pencil
HMH Physics Textbook
(optional)
Packet
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Technology Needs
Internet
Computer
HMH Online Resources
(optional)
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General Science 1B
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NAME:_________________________
CREDIT 2B: INTRODUCTION
Read “Four Fundamental Forces?” and watch the video “Magnet and Copper Tube” below. Then answer the
essential question.
Gravity and Electromagnetic Forces
Recall that a force is a push or pull upon an object. There are four
fundemental forces that govern the physics of the entire universe. In
this lesson you will study two of them: gravitational force and
electomagnetic force. Gravity and electromagnetism are forces that can
move objects without touching them. Instead, these forces create fields
that push and pull on objects. Because of this property, they are
described as “field forces.”
The reason objects fall towards Earth is because of gravity. In addition,
the influence of gravity is also related to why the sun shines and how a
system of planets and stars can remain in stable motion. The Earth is
one of many planets and other objects orbiting the sun. These planets
are part of a system surrounding the sun and their movement is
influenced by the sun’s massive gravitational pull.
The extremely small particles that make up these objects (atoms) are also governed by the same forces. All
atoms have an area surrounding their nucleus creating a magnetic push or pull, which influences other atoms
and objects near them. In both cases, the strength of the field force is stronger the closer the objects or atoms.
These forces decrease as the distance between them increases.
An essential question is something that allows you to explore the content of the credit. Before you answer the
essential question, watch the video. Then, answer the essential question to the best of your ability. You will
revisit the essential question at the end of the credit to see if your answer has evolved.
Video: Magnet and Copper Tube

“Copper pipe and neodymium magnet.” YouTube., 29 Mar. 2013. Web. 14 Oct. 2015.
Essential Question
How can one object affect the motion of another without touching it? Give a
specific example.
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General Science 1B
Credit 2
LESSON 2.1: GRAVITY
Learning Goal for this Credit
Communicate scientific information clearly, thoroughly and accurately.
Learning Goals for this Lesson
 Differentiate between mass and weight.
 Relate gravitational strength to mass and distance of objects.
Lesson Assignments
 Connect to Prior Knowledge
 Exploration Activity
 Reading Questions
 Videos (optional)
 Gravitational Force Simulation
 Review Questions
Engage
Connect to Prior Knowledge
Recall that objects at rest will only move when acted on by a force.
What causes leaves from a tree to fall towards the ground? With
that in mind, why doesn’t the Moon fall towards the Earth and
smash into it?
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Explore
Exploration Activity
What falls to the ground faster: heavier or lighter
objects? Locate a ruler and a paper clip. Hold one in
each hand. Drop them at the same time and observe
which lands on the floor first.
1. What did you observe?
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2. Using your knowledge of force, what can you
conclude about the force of gravity?
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Explain
As you complete the reading, answer the questions in the space provided.
Reading
What is the Difference Between Weight and Mass?
Before you study gravity, it is important to understand the difference between weight and mass. The terms
“mass” and “weight” are often used interchangeably in our daily speech, however, to an astronomer or a
physicist weight and mass are completely different. The mass of a body is a measure of how much matter it
contains. An object with mass has a quality called inertia. If you shake an object like a stone in your hand, you
would notice that it takes a push to get it moving and another push to stop it again. If the stone is at rest, it wants
to remain at rest. Once it is moving, it wants to stay moving. This quality or “sluggishness” of matter is its
inertia. Mass is a measure of how much inertia an object displays.
Weight is an entirely different concept. Every object in the universe with mass attracts every other object with
mass. The amount of attraction depends on the size of the masses and how far apart they are. For everydaysized objects, this gravitational pull is vanishingly small. In comparison, the pull between a very large object,
like the Earth, and another object, like you, can be easily measured. How? All you have to do is stand on a
scale! Scales measure the force of attraction between you and the Earth. This force of attraction between you
and the Earth (or any other planet) is called your weight. If you are in a spaceship far between the stars and you
put a scale underneath you, the scale would read zero. Your weight is zero. You are weightless. If there is a
boulder floating next to you, it is also weightless. Are you or the boulder without mass? Absolutely not. If you
grabbed the boulder and tried to shake it, you would have to push it to get it going and pull it to get it to stop. It
still has inertia, and hence mass, yet it has no weight. See the difference?
1. What is the difference between weight and mass?
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2. What is inertia?
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3. Why does a weightless object still have mass?
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What is the Law of Universal Gravitation?
Any two objects that have mass are pulled towards each other
by gravity. The strength of the gravitational force depends on
two things: the mass in each object and how far apart they are
from each other. The strength of gravity increases when the
mass of either object increases, and also becomes stronger the
closer the two objects are. Because this relationship applies to
all objects in the universe, it is referred to as the law of
universal gravitation.
4. Why is gravity called a universal force?
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5. As the distance between a planet and its moon increases, how does the gravitational force between them
change?
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Hipschman, Ron. “Your Weight on Other Worlds | Exploratorium.” Exploratorium: The Museum of Science, Art and Human Perception. N.p., 1997. Web. 11 Dec.
2015. .
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Videos
If you would like to learn more about this topic, then watch the videos below for more information.
(Optional)
John Young’s Lunar Salute on Apollo 16 (0:15)

“John Young’s Lunar Salute on Apollo 16.” YouTube. NASA.gov Video, 19 May 2013. Web. 11 Dec. 2015.
How is gravitational acceleration different on the moon? Watch astronaut John
Young pose for a jumping picture on the moon.
What’s the Difference Between Mass and Weight? (3:50)

How does gravity affect the weight of an object? This video will
explain the difference between mass and weight.
“Less Than Five – What’s the Difference Between Mass and Weight?.” YouTube. Astronimate, 25 Oct 2017. Web. 26 Apr.
2021.
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General Science 1B
Credit 2
Elaborate
Gravitational Force Simulation
Recall that gravitational strength is influenced by mass and distance. Open the following link to begin the
simulation. Follow the procedures below.
https://phet.colorado.edu/en/simulation/gravity-force-lab
Reid, Sam, John Blanco, Noah Podolefsky, Carl Wieman, Wendy Adams, and Patricia Loeblien. “Gravity Force Lab.” PhET. University
of Colorado, 2015. Web. 14 Dec. 2015.
Procedure:
1. Uncheck the box in the lower right that says “show values” in the lower-right.
2. Gravitational strength will now be represented by the length of the arrows. The longer the arrow, the
greater the force that is attracting the objects.
3. You can alter the mass of two objects (in kilograms) and the distance between them (in meters).
4. The masses and distances in this simulation are similar to objects in the room with you.
Analysis:
Answer the following questions using the simulation.
1. Increase the mass of one or both objects. How does this change the gravitational force between them?
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2. Pull the objects further apart. What happens to the gravitational force?
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3. How would you maximize the gravitational force in this simulation? What are the distance and mass
values?
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Evaluate
Review Questions
Answer the following questions.
1. How does the force of gravity change as the mass of one object doubles?
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2. What do you think will happen if the distance between the two object is cut in half?
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3. Which is more important for determining gravitational force: mass or the distance between two objects?
Explain your answer.
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General Science 1B
Credit 2
LESSON 2.2: ORBIT
Learning Goal for this Credit
Communicate scientific information clearly, thoroughly and accurately.
Learning Goals for this Lesson
 Identify causes of satellite motion.
 Predict how objects will come to orbit larger ones.
Lesson Assignments
 Newton’s Thought Experiment
 Exploration Activity
 Reading and Questions
 Videos (optional)
 Gravity and Orbit Simulation
 Review Questions
Engage
Newton’s Thought Experiment
Imagine you put a cannon on the top of a very tall mountain. You
start firing cannonballs horizontally. Each time you add more
gunpowder to the cannon, which makes the next cannonball travel
further before hitting the ground. Is it possible that at some point
the cannonball will miss the ground? What does this have to do
with the orbit of the moon?
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If you need help answering the question above, follow the link below to shoot a simulated cannon and test
Newton’s thought experiment yourself.
http://spaceplace.nasa.gov/how-orbits-work/en/
“Shoot a Cannonball into Orbit!” NASA Space Place. NASA, 2015. Web. 14 Dec. 2015.
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Explore
Exploration Activity
If you drop a stone, it will fall in a straightline path to the ground below. If you move
your hand horizontally as you drop the stone,
it will follow a curved path to the ground. If
you move your hand faster, the stone will
land farther away and the path it travels will
not curve as sharply. What would happen if
the curvature of the path matched the
curvature of the Earth? Simple: you would
have created an Earth satellite.
An object will orbit a larger object due to
two vectors of movement force. An object in
motion will stay in motion, continuing to
move forward. Earth’s gravity will pull an
object straight down. With these two forces
acting on an object simultaneously, satellite
motion or orbit can occur. An Earth satellite
is an object that falls around the Earth,
rather than into it (as you do when you
jump).
Answer the questions below.
1. Explain how a satellite is able to orbit Earth without falling to the surface.
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2. What would happen to a satellite if its orbit speed was reduced by half?
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3. What would happen to a satellite if its orbit speed doubled?
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Adapted from Hewitt, Paul G. Conceptual Physics. Upper Saddle River, NJ: Prentice Hall, 2006. Print.
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General Science 1B
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Explain
As you complete the reading, answer the questions in the space provided.
Reading
What is an Orbit?
An orbit is a regular, repeating path that one object in space takes around
another object. An object in an orbit is called a satellite. A satellite can be
natural, like Earth or the moon. Many planets have moons that orbit them. A
satellite can also be man-made, like the International Space Station. Planets,
comets, asteroids and other objects in the solar system orbit the sun. Most of
the objects orbiting the sun move along or close to an imaginary flat surface.
This imaginary surface is called the ecliptic plane.
1. What is a satellite?
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2. Why is Earth an example of a satellite?
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What Shape Is an Orbit?
Orbits come in different shapes. All orbits are elliptical, which means they are an ellipse, similar to an oval. For
planets, orbits are almost circular. In comparison, the orbits of comets have a different shape. They are highly
eccentric or “squashed.” They look more like thin ellipses than circles.
Satellites that orbit Earth, including the moon, do not always stay the same distance from Earth. Sometimes they
are closer, and at other times they are farther away. The closest point a satellite comes to Earth is called its
perigee. The farthest point is the apogee. For planets, the point in their orbit closest to the sun is perihelion.
The farthest point is called aphelion. Earth reaches its aphelion during summer in the Northern Hemisphere.
The time it takes a satellite to make one full orbit is called its period. For example, Earth has an orbital period
of one year. The inclination is the angle the orbital plane makes when compared with Earth’s equator.
3. What is Earth’s orbital period around the sun?
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How Do Objects Stay in Orbit?
An object in motion will stay in motion unless something pushes or pulls on it. This statement is called
Newton’s first law of motion. Without gravity, an Earth-orbiting satellite would go off into space along a
straight line. With gravity, it is pulled back toward Earth. A constant tug-of-war takes place between the
satellite’s tendency to move in a straight line, or momentum, and the tug of gravity pulling the satellite back.
An object’s momentum and the force of gravity have to be balanced for an orbit to happen. If the forward
momentum of one object is too great, it will speed past and not enter into orbit. If momentum is too small, the
object will be pulled down and crash. When these forces are balanced, the object is always falling toward the
planet, but because it’s moving sideways fast enough, it never hits the planet. Orbital velocity is the speed
needed to stay in orbit. At an altitude of 150 miles (242 kilometers) above Earth, orbital velocity is about 17,000
miles per hour. Satellites that have higher orbits have slower orbital velocities.
4. Explain Newton’s first law of motion.
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Where Do Satellites Orbit Earth?
The International Space Station is in The
International Space Station is in low Earth orbit, or
LEO. LEO is the first 100 to 200 miles (161 to 322
km) of space. LEO is the easiest orbit to get to and
stay in. One complete orbit in LEO takes about 90
minutes.
Satellites that stay above a location on Earth are in
geosynchronous Earth orbit, or GEO. These
satellites orbit about 23,000 miles (37,015 km) above
the equator and complete one revolution around
Earth precisely every 24 hours. Satellites headed for
GEO first go to an elliptical orbit with an apogee
about 37,015 km. Firing the rocket engines at apogee then makes the orbit round. Geosynchronous orbits are
also called geostationary.
Any satellite with an orbital path going over or near the poles maintains a polar orbit. Polar orbits are usually
low Earth orbits. Eventually, Earth’s entire surface passes under a satellite in polar orbit. When a satellite orbits
Earth, the path it takes makes an angle with the equator. This angle is called the inclination. A satellite that
orbits parallel to the equator has a zero-degree orbital inclination. A satellite in a polar orbit has a 90-degree
inclination.
5. Explain the difference between LEO and GEO.
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Why the Moon is Getting Further Away from Us?
It’s easy to take the Moon for granted, even on a clear night when it can light up the sky. It really feels as if it
has always been there just as it is now. However, that is not necessarily true. It is thought that the Moon was
formed when a proto-planet about the size of Mars collided with the early Earth around 4.5 billion years ago.
The debris left over from impact came together to form the Moon. Computer simulations of such an impact are
consistent with the Earth-Moon system we see in the 21st Century. The simulations also imply that at the time
of its formation, the Moon sat much closer to the Earth – a mere 22,500km (14,000 miles) away, compared with
the quarter of a million miles (402,336 km) between the Earth and the Moon today. The Moon continues to spin
away from the Earth, at the rate of 3.78 cm (1.48 in) per year, which is the same speed at which our fingernails
grow. Without the Moon, the Earth could slow down enough to become unstable, but this would take billions of
years and it may never happen at all.
The migration of the Moon away from the Earth is mainly due to the action of the Earth’s tides. The Moon stays
in orbit by the gravitational force that the Earth exerts on it, but the Moon also exerts a gravitational force on
our planet. This causes the movement of the Earth’s oceans to form a tidal bulge. Due to the rotation of the
Earth, this tidal bulge actually sits slightly ahead of the Moon.
Some of the energy of the spinning Earth gets transferred to the
tidal bulge via friction. This drives the bulge forward, keeping it
ahead of the Moon. The tidal bulge feeds a small amount of
energy into the Moon, pushing it into a higher orbit like the faster,
outside lanes of a test track. This phenomenon is similar to the
experience one feels on a children’s merry-go-round. The faster it
spins the stronger the feeling of being slung outwards. As a result,
the energy gained as the Moon is pushed higher is balanced by a
reduction in the energy of its motion – so an acceleration provided
by the Earth’s tides is actually slowing the Moon down. While
3.78 cm may not seem like much, this small difference over a
long enough period of time could affect life on Earth, making the
planet slow down.
On early Earth, when the Moon was newly formed, days were five hours long, but with the Moon’s braking
effect operating on the Earth for the last 4.5 billion years, Earth days have slowed down to the 24 hours that we
are familiar with now, and they will continue to slow down in the future. We can see some evidence of the
slowdown in the fossil records. By looking at the daily growth bands of corals we can calculate the numbers of
days that occurred per year in past periods, and from this we can see that days are getting longer, at a rate of 19
hours every 4.5 billion years. The length of a day, or in other words the rotation speed of the planet, plays a big
part in its stability. Just like keeping a plate spinning on a stick, the key is to have the plate spinning fast. If it
slows down, the plate crashes to the floor. In a similar way, as the Earth’s rotation slows down, our whole planet
may start to slowly wobble and this will have a devastating effect on our seasons.
Earth’s seasons are due to the Earth’s tilt at an angle of 23 degrees on its axis. During summer, the Northern
Hemisphere is tilted towards the sun which results in longer days and warmer weather. In contrast, during
winter the Northern Hemisphere is tilted away from the sun giving which results in shorter days and cooler
weather. If this were to change, and the Earth became unstable, then parts of the world could experience greater
temperature swings throughout any given year, with freezing Arctic temperatures in winter followed by blazing
hot temperatures in summer.
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As humans we have the ability to adapt to our local surroundings to meet our needs. If humans are still around
when and if it happens it is quite likely we would survive these massive changes with air conditioning in the
summer and a lot of heating in winter. Unfortunately, most animals are not so adaptable and if these changes
happened rapidly due to an unstable planetary wobble, then most animals would not be able to evolve quickly
enough to hibernate or migrate out of harm’s way. The human race has little to fear at present. By the time any
change occurred, humans might even have generated technology that could speed up the Earth’s rotation or
transport us to other livable planets within our galaxy.
6. How is the Moon thought to have formed?
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7. What is causing the Moon to move further away from us? How fast is it happening?
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8. What effect has the Moon had on the Earth’s rotation? What evidence is there to support that?
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9. How does the Moon affect the Earth’s seasons?
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Dunbar, Brian. “What Is Orbit?” NASA, NASA, 1 June 2015, www.nasa.gov/audience/forstudents/5-8/features/nasa-knows/what-is-orbit-58.html.
“Why the Moon Is Getting Further Away from Earth – BBC News.” BBC News. N.p., 1 Feb. 2011.
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Videos
If you would like to learn more about this topic, watch the videos below for more information. (Optional)
Gravity for Astronauts in Orbit (7:11)

“Gravity for Astronauts in Orbit.” Khan Academy. YouTube, 20 June 2011. Web
Is gravity acting on astronauts in space? Check out how gravitational
force effects astronauts while they circle the Earth. (Where have you
seen that equation before?)
Cool Science – Defining Gravity (4:05)

“Cool Science – Defining Gravity.” Science North. YouTube, 28 Sept. 2010. Web
Why do these objects end up in the center in this simulation when they
wouldn’t in space? Hint: we’ve already learned about this!
Orbit can be demonstrated with some ball bearings and a funnel. Notice
how objects accelerate when they get closer to the center from the
greater force.
Why Do Astronauts Feel Weightless? (2:49)
https://www.youtube.com/watch?v=EJZ2rezjFps
“Why do astronauts feel weightless?” YouTube. The Curious Engineer, 1 Dec 1, 2012. Web.
Why is it wrong to refer to orbital environments are “zero gravity?” Why
do people in orbit appear as if there is no gravity? This video will
explain why astronauts feel weightless in space.
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General Science 1B
Credit 2
Elaborate
Gravity and Orbit Simulation
Open the PhET simulation:
http://phet.colorado.edu/en/simulation/gravity-and-orbits
Podolefsky, Noah, Emily Moore, Kathy Perkins, Patricia Loeblien, Sam Reid, Jon Olson,
Chris Malley, and John Blanco. “Gravity and Orbits.” PhET. University of Colorado, 2015. Web. 14 Dec. 2015.
Procedure:
1. Once you have followed the link and opened the simulation, choose the “Gravity and Orbits Model”
option.
2. In the right hand menu, choose the Earth and Moon option. The Earth and Moon should now be visible
on the screen.
3. Make sure “Gravity” is turned on.
4. Click the Gravity Force, Velocity, and Path boxes so that these are all checked.
5. Press the play button.
6. Use the simulation to answer the questions below.
Analysis:
1. What shape does the orbit of the Moon around the Earth appear to be?
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2. Using the slider bars, increase the Earth’s mass to 1.5. What changes to the Moon’s orbit do you notice?
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3. Now increase the Earth’s mass to 2. What happens? Explain why this occurred.
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4. Reset the simulation by clicking the grey reset button in the top right. Decrease the Earth’s mass to 0.5.
What happened? Explain why this occurred.
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Evaluate
Review Questions
Answer the following questions.
1. If the Moon’s mass increased, how would this affect Earth’s tidal bulge?
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2. The period it takes the Moon to orbit the Earth is approximately 27 days. If the Moon’s mass was
increased, would the period increase or decrease? Explain your answer.
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3. Would it be possible for a satellite to cross orbital paths with the moon? Why or why not?
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General Science 1B
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LESSON 2.3: MAGNETISM
Learning Goal for this Credit
Communicate scientific information clearly, thoroughly and accurately.
Learning Goals for this Lesson
 Describe how magnetic fields influence magnetized objects.
 Predict how magnetized objects move given their orientation.
Lesson Assignments
 Connect to Prior Knowledge
 Exploration Activity
 Reading and Questions
 Videos (optional)
 Compasses and Magnetic Fields
 Review Questions
Engage
Connect to Prior Knowledge
What do you think causes magnets to stick to a refrigerator? Why do
other objects fall when placed in the same location?
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Explore
Exploration Activity
Magnets generate fields that travel from their north pole to their south
pole. This means that when two magnets are placed near each other, they
will be pulled together (attracted) or pushed apart (repelled). When the
north side of one magnet faces the south side of another, these opposite
sides will attract. If two north or two south sides face each other, these
like-sides will repel.
In the following examples, determine if the two magnets would attract or
repel. Write attract next to the magnets that would attract and repel next
to the magnets that would repel.
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Explain
As you complete the reading, answer the questions in the space provided.
Reading
How Do Magnets Work?
Magnets exert force on one another. They can attract or
repel each other depending on which side one is facing
towards another. Just as with electric charges and gravity,
magnetism is a field force and the strength of two magnets’
interaction depends on the distance between them. These
magnetic fields are generated at the magnetic poles. All
magnets have both a north pole and south pole generating
opposite fields. When two opposite fields, one north and
one south, come into contact with each other the force pulls
them together. When two of the same fields, both north and
south, are near each other they push away. When trying to
push two magnets together with the same poles facing each
other, you will feel them repel in opposite directions.
Magnetic poles are caused by direction, either north or
south, that the atoms in the magnet are pointing. These
atoms are grouped together in domains, with each atom in
a domain pointing in the same direction. In a nonmagnetized material, these domains point in random
directions, cancelling each other out. When a material is
magnetized by another nearby magnet, these domains turn,
and all face the same direction. When all of the domains
are oriented the same way, the object becomes magnetized and will have a north and south pole. This object
will now produce a stronger magnetic field of its own.
Weebly, Michael. “Magnets Domains.” ACA Grade 8 Science. ACA, n.d. Web. 14 Dec. 2015. .
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1. Explain why magnets have poles.
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2. How does a magnet generate a magnetic field?
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3. What directions do magnetic domains point in a magnet compared to those that are non-magnetized?
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Videos
If you would like to learn more about this topic, watch the videos below for more information. (Optional)
Magnets: How Do They Work? (6:25)

“MAGNETS: How Do They Work?” YouTube MinutePhyics. 23 Sep. 2013. Web. 2 Nov 2015
Interested in having a deeper understanding of magnets? Check out this
video to get more detail on what makes them function.
Simple Electric Train (1:44)

“World’s Simplest Electric Train.” YouTube. AmazingScience, 1 Mar. 2015. Web. 2 Nov 2015.
Do you have two magnets, a battery and some copper wire? Then you
have all that’s needed to make your own train! What’s causing this train
to move?
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General Science 1B
Credit 2
Elaborate
Compasses and Magnetic Fields
Part I: Magnetic Compasses
A compass is a simple magnetic device used to detect magnetic fields. It is made of a magnet that can rotate to
point towards another magnetic pole. The shaded side of the compass is the north side, meaning that it will
point towards the south side of any magnet it is near. (Recall that the north pole will attract the south pole.)
Directions:
In the following scenarios, use the compass image to determine the north and south poles of the magnet, and
then fill in “N” for north and “S” for south. The first example has been filled in for you.
1. Example
2.
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General Science 1B
Credit 2
3.
4.
5.
6.
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General Science 1B
Credit 2
Part II: Magnetic Fields
The space around a magnet, in which a magnetic force is exerted, is filled with a magnetic field. The shape of
the field is revealed by magnetic field lines. Magnetic field lines spread out from one pole, curve around the
magnet, and return to the other pole. The direction of the field outside the magnet is from the north to the south
pole. Where the lines are closer together, the field strength is greater. Magnetic field strength is greater at the
poles, as seen in the diagram below. If another magnet or small compass is placed anywhere in the field, its
poles will tend to line up with the magnetic field.
Directions:
The diagrams on the next three pages show where a compass points when placed at locations close to, and all
around a magnet. Using the compass pointers as your guide, draw the magnetic field lines surrounding the
magnet. The first diagram below has been done for you as an example.
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General Science 1B
Credit 2
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General Science 1B
Credit 2
“Earth’s Magnetic Field.” Earth’s Magnetic Field – Interactive Simulations, EduMedia, 2017, www.edumedia-sciences.com/en/media/260-earths-magnetic-field.
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General Science 1B
Credit 2
Evaluate
Review Questions
Answer the following questions.
1. Explain how you would know if two magnets will attract or repel one another.
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
2. If you break a magnet in half, where will the north and south ends be on the two new smaller magnets?
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
3. If a magnet sticks to an object, such as a refrigerator or a paper clip, what does that tell you about those
objects compared to those the magnet will not stick to?
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
4. If a compass is not placed near a magnet, the north side of the compass will point towards the Earth’s
North Pole. What does that tell you about the magnetic charge of the North Pole?
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
Revisit the essential question, did your answer change? Why or why not?
Essential Question
How can one object affect the motion of another without touching it? Give a specific example.
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
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General Science 1B
Credit 2
Learning Goal for this Credit
Communicate scientific information clearly, thoroughly and accurately.
Lesson
2.1
Title
Gravity
2.2
Orbit
2.3
Magnetism
Learning Goals For Each Lesson

Differentiate between mass and weight.

Relate gravitational strength to mass and distance of objects.

Identify causes of satellite motion.

Predict how objects will come to orbit larger ones.

Describe how magnetic fields influence magnetized objects.

Predict how magnetized objects move given their orientation.
General Science Rubric
Credit Grading
Responses to Packet
and Questions
40 pts.
Performance Task
40 pts.
Quiz
20 pts.
4
 My responses in
my packet show
clear reasoning and
use of evidence.
3
 My responses in
my packet show
basic reasoning and
use of evidence.
2
 My responses in
my packet show
basic reasoning but
limited evidence to
support it.
1
 My answers to the
questions in my
packet are either
unscientific or
overly simplistic,
and have limited
evidence.
 I completed some
of the expectations
of the assignment
to show what I
know.
 I completed some
of the expectations
but struggled to
show what I know.
 I made connections
to other ideas
within and across
science credits.
 I completed all of
the expectations of
the assignment to
thoroughly show
what I know.
 My explanation is
clear and supported
by valid scientific
evidence.
 I mainly completed
the expectations of
the assignment to
show what I know.
 My explanation is
supported by
scientific evidence.
 My explanation is
simplistic or basic
and supported by
limited scientific
evidence.
 My explanation is
not supported by
scientific evidence.
Students receive 2 points per correct response.
___x 10 = ___/40
___x 10 = ___/40
___x2 = ___/20
Total:
___/100
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General Science 1B
Credit 2