Math Concept Reader MCR g6 listening to the world of science

Math Concept Reader

Listening to the World of Science

Math Concept Reader

Walk the Distance

by Jennifer Marrewa

DIGITAL FINAL PROOF

by Carri Stuhr

Listening to the

World of Science

Math Concept Reader

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Chapter 1:

Sound Science



Kaja grabs her coat and backpack from her locker and hurries down the hall to the school’s media center She is going to the Science Club meeting The Science Club meets once a week Ms Wilson, the group’s leader, is a science teacher at the school who helps students in the club explore science through different activities

When Kaja arrives, she sees other club members standing around a computer looking at digital photographs of some

of the activities the Science Club members participated in last year There is a picture of Mariana looking through a microscope Another photo shows Kim and Julia standing next to a pond with jars in their hands There is also a photo

of Henry working on a Science Fair project Kaja sees a picture of herself standing in front of a science museum

A Science Club member enjoys

a night of stargazing.

Ms Wilson asks the students to look at the photographs and talk about their favorite activities from last year Kaja says she liked learning about the solar system on the club’s trip to

a science museum Mariana thought it was interesting

to study how wind can generate electricity Jayden says that he learned how to identify several constellations after he spent a night stargazing with the Science Club As the students talk,

Ms Wilson writes these topics on the board

“The Science Club participates in many activities,” says

Ms Wilson “We also get to learn a lot of amazing things about science The beginning of the year is a great time to share our experiences with other students I want us to work on a project that will encourage more students to participate in the Science Club.”

Podcasts can be downloaded onto

an audio player.

Ms Wilson thinks it would be fun for the Science Club to create podcasts about their favorite science topics A podcast

is an audio or video recording The students will create audio podcasts and post them on the club’s Web page Students at school, and even the public, can go to the Web page and download the podcasts to an audio player or a computer Then they can listen to the reports on different science topics

The group starts to talk about their experiences with podcasting Jayden says he listens to podcasts on the computers

in the media center Kaja says she knows of a Web page where students share podcasts Most of the students have listened to podcasts This is their first time making one, though! Everyone wants to try making a podcast They can share what they have learned about science with other students in the school

Ms Wilson discusses writing podcasts with her class.

Ms Wilson says the first step is to select a topic they want to share with other students She points to the ideas the students listed as their favorite activities She encourages the group to choose topics that other students may want to hear more about Once the students have selected a topic, they can research, write and record the podcasts

Ms Wilson suggests that students make their podcasts about ten minutes long The first part of the podcast should

be an introduction The next part of the podcast should cover two or three main points They should finish the podcast with

a summary of what has been talked about already

Ms Wilson gives the group advice on writing a podcast

“It is important to keep the listener in mind,” she says “Help the listener understand the science through the words you choose, and make your writing style fun and engaging The listener will stay interested if you share information and give examples.”

Chapter 2:

Writing

a Podcast

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Apparent Magnitude Scale



The students break into groups to write their podcasts Julia and Jayden talk about the night the Science Club went stargazing They used a telescope to see the stars and several planets They also learned the names and positions of several constellations They think other students would be interested in a podcast about the night sky and its stars

The podcast will describe how scientists measure the brightness of stars Then it will describe how to find constellations in the night sky

Julia opens her science book to look for more information on the brightness of stars She finds a chart that shows the apparent magnitude

of stars on a scale from one to six Apparent magnitude measures how bright a star appears to the human eye on Earth

The scale was created by Hipparchus, an ancient Greek astronomer who used the scale to describe the brightness of the stars A star with a smaller magnitude is actually easier to see than one with a larger magnitude A star with a magnitude of 1 is much brighter than a star with a magnitude of 6

Name Apparent Magnitude

Betelgeuse 0.50 Castor 1.57 Altair 0.77 Deneb 1.25 Polaris 2.02 Pollux 1.14 Riegel 0.12 Vega 0.03

Stars and their Apparent Magnitude

Jayden thinks they should tell listeners the apparent magnitude of

stars that are easy to find He looks through a book and finds a chart

with the names of stars and their apparent magnitudes

Julia points to the apparent magnitude of Polaris, the North Star

Its apparent magnitude is 2.02 She also finds the apparent magnitude

of Vega, a star that shines brightly in the summer sky Vega has an

apparent magnitude of 0.03 Julia subtracts the apparent magnitude

of Vega from the apparent magnitude of Polaris

2.02

– 0.03

1.99

The difference in apparent magnitude between the two stars is

1.99 Based on the subtraction, Julia estimates there are about two

units of apparent magnitude between the two stars

Julia reads that as you move down one unit on the apparent

magnitude scale, a star becomes 2.5 times brighter To find out how

much brighter Vega is than Polaris, she multiplies 2.5 by 2.5 to find

the product

2.5 × 2.5 = 6.25

Jayden says, “Based on our calculation, we can say that Vega

appears to be about six times as bright as Polaris We can post the

apparent magnitude scale on the club’s Web page, and then we can

tell listeners where to find the scale.”

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Wind turbines capture energy from the wind.

Mariana and Kim want to write a podcast about wind energy

Last year, the Science Club visited a wind farm where wind

turbines are used to harvest the power of wind energy A turbine

is a type of modern windmill that looks like a giant tower with

large blades on the top A turbine turns the energy from the wind

into electricity

“We can start the podcast with some basic facts about wind

energy as an alternative energy source,” Mariana says “Then we

can talk about how much energy a turbine makes.”

At the wind farm, the girls learned that the wind has been a

source of energy for many years Farmers once used the energy

from windmills to grind grain and pump water from the ground

In the 1930s, windmills generated electricity

The wind turbines built today operate on the same principle

as windmills Wind turns the giant blades of the turbine The

turning blades operate a generator that produces electricity Power

companies use power lines to collect the electricity produced by

wind farms Wind turbines in the United States produce enough

energy to power 1.6 million homes

Kim and Mariana discover that three wind turbines can provide electricity for many homes.

Turbine Energy Produced (in kWh)

Turbine A 271,604 Turbine B 189,307 Turbine C 170,525 Total for Turbines A, B, and C 631,436

Kilowatt Hours of Energy Produced by Three Wind Turbines in One Month

Kim and Mariana collected data from three wind turbines on the farm when

they visited it last year They find the data and look at their notes The data show

how many kilowatt hours (kWh) of energy the wind turbines produced in one

month A kilowatt hour is a measure of how much energy is used or produced

Wind turbines generate a great deal of energy! These three turbines generate a

total of more than 600,000 kilowatt hours of energy each month

Mariana thinks an example would be helpful because it will make the

data easier to understand She thinks they should say how many homes

600,000 kilowatt hours of energy will power for one month

Kim looks at data about home energy use on the Internet Suppose that an

average home uses about 900 kilowatt hours each month Kim and Mariana

write an equation to help them estimate how many homes could be powered

by the three turbines

630,000 ÷ 900 = 700

“We can say that three turbines provide enough energy each month for

about 700 homes,” Mariana says

Kaja and Henry will write a podcast about the distances between the planets and other objects in the solar system.

Kaja and Henry agree that their favorite activity last year was the trip to a science museum They saw a movie on the solar system at the museum’s planetarium A planetarium is a domed theater which displays the position of stars and planets

on a large screen

Kaja wants to write a podcast that takes students on an audio journey through the solar system Kaja and Henry could describe the distance between the sun and the planets This might help students realize the large difference in distances between objects in the solar system

Henry sits down at the computer to search for information He finds a table It lists the distances between the sun and the planets He picks two distances as examples

The table shows that the distance from the sun to Earth is 150,000,000 kilometers Neptune is about 4,498,000,000 kilometers from the sun

Kaja says it would be easier to use scientific notation to compare these distances She opens a notebook and writes both numbers in standard form and in scientific notation

150,000,000 = 1.5 × 108

4,498,000,000 = 4.498 × 109

Planet Distance from the sun (in kilometers)

Mercury 58,000,000 Venus 108,000,000 Earth 150,000,000 Mars 228,000,000 Jupiter 778,000,000 Saturn 1,427,000,000 Uranus 2,871,000,000 Neptune 4,498,000,000

Approximate Distance From the Sun to the Planets

Henry agrees that scientific notation is helpful for writing large numbers He thinks there may be another way to help listeners understand the distances between the planets Henry remembers the Science Club made a model of the solar system It helped them understand the distance between the planets on a much smaller scale To create a scale, they divided each distance by the same number It might be easier to describe the distances in the podcast if they used a smaller scale He uses the scale of 1,000,000 km equals 1 m

Kaja and Henry divide the distance from the sun to Earth by 1,000,000 Then they divide the distance from the sun to Neptune by 1,000,000 This tells them the scale distance in meters

150,000,000 ÷ 1,000,000 = 150 4,498,000,000 ÷ 1,000,000 = 4,498 Using this scale, Earth would be about 150 meters from the sun Neptune would be about 4,498 meters from the sun!

Kaja and Henry will use the same scale to find the distance between the sun and the other planets These measurements will help listeners compare the distances

Chapter 3:

Ready, Set Record

1

At the next Science Club meeting, students finish writing their podcasts Each group gives its script to a review group

The review group offers suggestions for changes

“How did you choose the scale for the planets?” Jayden asks Kaja and Henry “You might want to include your scale

on the club’s Web page.”

“I liked your podcast on stargazing,” Kaja says to Julia and Jayden “I thought you could add a sentence about which planets you can see in the night sky I know that Venus is a planet that you can find in the sky on a clear night.”

Ms Wilson asks each group to read its script aloud This will help them find the length of their podcast When they finish reading, other members of the Science Club can comment on the podcast

“As you listen to the podcast, ask yourself if there is anything you did not understand,” Ms Wilson suggests “Think about whether or not you would like something explained in more detail.”

Kim reads her part of the podcast on wind energy.

Kim and Mariana volunteer to read their podcast They start their podcast with an introduction

Then they describe their visit to the wind farm They explain how much energy the three wind turbines make Finally, the girls say how much energy a family uses each month

Kim and Mariana ask for input from the other students

Jayden thinks they did a great job of describing the wind farm

Kaja liked the podcast She says it helped her understand just how much energy turbines can make

Ms Wilson found it interesting to hear how much energy

a family uses in one month She has a suggestion The students could talk about how much energy an appliance uses in one day

She gives the example of a fan that uses 100 watts of electricity It

is used for three hours each day Ms Wilson multiplies 100 by 3 to find the total number of watts

“A 100 watt fan that operates for three hours uses 300 watts

of electricity a day,” says Ms Wilson “You could compare this amount to the electricity used by a larger appliance, such as a refrigerator or a stove.”

Jayden and Julia use a computer and software

to record their podcast.

The students are ready

to record their podcasts

Julia and Jayden open a program on the computer

It will help them make their podcast Julia clicks the record button She starts to read the first part

of their podcast She clicks the stop button She looks

at a counter on the screen that shows that her part took 210 seconds Julia divides 210 by 60 seconds in one minute to find the length of her part in minutes

210 ÷ 60 = 3.5 Julia’s part of the podcast is 3.5 minutes long

Jayden clicks the record button and the counter continues

to add seconds When Jayden finishes, they have recorded for a total of 570 seconds

Julia subtracts to find the length of Jayden’s part

570 – 210 = 360 Jayden’s part of the podcast lasts 360 seconds Julia and Jayden want to find how many minutes are equal to 360 seconds Julia divides the number of seconds by 60 seconds

360 ÷ 60 = 6 The total length of Jayden’s part is six minutes

The next step is to find the total length of their podcast

6 + 3.5 = 9.5 Their podcast is 9.5 minutes long