Introduction to MasteringAstronomy + Ch 1

Introduction to MasteringAstronomy + Ch 1

Due: 9:00am on Tuesday, September 27, 2011

Note: You will receive no credit for late submissions.

To learn more, read your instructor's Grading Policy

[Switch to Standard Assignment View]

[ Print ]

The purpose of the following five exercises is to familiarize you with the system you will be using for the rest of your course. These exercises are not intended to teach or test your knowledge of any specific subject material. Therefore, you will not be penalized for using hints or submitting incorrect answers.

Welcome to Mastering Questions

Welcome to Mastering!

Mastering presents homework items assigned by your instructor and works with you to answer them. Items typically have an introduction, possibly figures, and one or more parts for you to answer.

Part A

(The link above tells you that this Part has an illustration.)

How many months of the year have 28 days?

ANSWER:

1

2

12

It depends on whether or not it is a leap year.

Answer not displayed

Part B

Part not displayed

Part C


Introduction to Numeric Answers

This exercise is not intended to test your knowledge of any specific subject material. Therefore, on this problem you will not be penalized for using hints or submitting incorrect answers.

Overview

When an assignment question requires that you enter a numeric answer, you will see an answer box like the one illustrated here.

To answer this type of question, you will need to type the numeric value for distance in the rectangle between the quantity you are solving for

(distance) and the units (meters).

In addition to typing alphanumeric values from your keyboard, you can enter non-numeric information by using either the menu tabs above the rectangular answer box (for more information click Help ) or

the equivalent key strokes, as listed in the Shortcuts menu.

Grading

Tolerance

For grading, your numeric answers often (but not always) can be within a tolerance range of the official answer. For example, if the answer to a numeric problem with a tolerance of 2% were 105, answers between 103 and 107 would be graded as correct.

If you submit an answer that is rounded to within the grading tolerance but is not the exact answer, you will receive full credit. If this value is needed in future parts keep all the digits and round as the final step before submitting your answer.

Significant figures

Most questions with numeric answers will require your answer to be given to at least three digits or significant figures.

Your answer may be graded as incorrect if you have calculated correctly but then rounded your final answer to too few digits. If a different number of significant figures is required, this will be part of the question's answer instructions.

When you need to do multiple calculations to get an answer, use more significant figures than required in each calculation and round at the end only. Rounding too early can cause your final answer to be outside the tolerance range.

Part A

For most answers, you will simply enter your numeric answer directly into the space provided to the right of the equal sign. Answer the following question by typing the numeric answer into the answer box.

If you have a gross of items, you have 144 items. If you buy a gross of eggs, how many dozen eggs do you have?

Hint A.1

How many items are in a dozen?

Hint not displayed

Express your answer in dozens. Do not enter the units; they are provided to the right of the answer box.

ANSWER:

number of eggs = Answer not displayed

Part B

When entering large numbers in the answer box, do not use commas. For example, enter 1276400 for the number 1,276,400. Do not enter

1,276,400 . If you accidentally enter commas, you will get a message that your answer has the wrong number of terms. Answer the following question by typing the numeric answer into the answer box.

What is the sum of 9260 and 3240?

Hint B.1

How to compute the sum


Express your answer numerically to at least three significant figures.

ANSWER:

sum = Answer not displayed

Scientific notation

You may want to enter 367,000,000 in scientific notation as .

Instead of the symbol, use a multiplication dot ( ) by typing the keyboard multiplication symbol * (Shift + 8).

To input the exponent for numbers written in scientific notation, do either of the following:

Click the button found under the

Type ^ (Shift + 6) from your keyboard.

For example,

menu.

can be entered in the answer box by typing 3.67*10^8 .

Part C

Practice entering numbers in scientific notation by entering the diameter of a hydrogen atom in its ground state, the answer box.

Express the diameter of a ground-state hydrogen atom in meters using scientific notation. Do not enter the units; they are provided to the right of the answer box.

ANSWER:

=


, into

Part D

If you are asked to provide a set of two or more numeric answers, separate them with commas. For example, to provide the year that Sputnik

(the first satellite to be sent into orbit around the Earth) was launched and the year humans first walked on the Moon, you would enter

1957,1969 in the answer box.

A rectangle has a length of 5.50 and a width of 12.0 . What are the perimeter and area of this rectangle?

Hint D.1

How to find the perimeter


Hint D.2

How to find the area


Enter the perimeter and area numerically separated by a comma. The perimeter should be given in meters and the area in square meters. Do not enter the units; they are provided to the right of the answer box.

ANSWER:

perimeter, area = Answer not displayed

,

Introduction to Significant Figures

Many questions in Mastering require you to enter your answer to a specified number of significant figures. For grading purposes, some numeric answers must be exact. Suppose you are asked "How many days are in a week?" The answer must be "7." Other numeric answers may be graded as correct not only when they match the exact answer but also if they fall within an acceptable range of the exact answer. This range is known as the grading tolerance. Suppose you are asked "How many days are in a year?" The precise answer is 365.24 days. However, a calendar contains 365 days, so the Mastering system will also accept that as correct.

An answer that falls within the Mastering grading tolerance will also be marked as correct and you will be given full credit. You will see a feedback box that looks like the one below:

Because you rounded differently than the system did, your rounded answer might affect your work on further calculations in the same item and could cause your next answer to fall outside of the tolerance. To prevent this, you will be asked to use the unrounded answer for all future parts.

Part A

Suppose you are asked to find the area of a rectangle that is 2.1 wide by 5.6 long. Your calculator answer would be 11.76

Now suppose you are asked to enter the answer to two significant figures. (Note that if you do not round your answer to two significant figures, your answer will fall outside of the grading tolerance and be graded as incorrect.)

Enter your answer to two significant figures and include the appropriate units.

.

ANSWER:


Transition will be visible after you complete previous part(s).

Part B


Part C


Part D


Introduction to Multimedia in Mastering

You may have Assignments that require you to investigate a piece of media prior to answering questions. Remember that the media is available to help you understand the material, so you should always look at it first before you try to answer the questions.

Part A Embedded Animations

Sometimes the animation will be on the screen and you have to click on it to make it start. Click on the image to watch the animation.

Which shape ends up in the box at the end of the clip?

ANSWER: triangle circle

I don’t see anything.

polygon square star


Part B Pop-Up Animations

Some types of media may open in a new browser window. Watch this animation and then come back to this window to find the question you need to answer. Click here to open the animation.

What is the final shape of the dots in the pop-up animation?

ANSWER:

I don’t see a pop-up window.

circle rectangle square star


Part C Audio Clips

Click on the arrow to play the audio file, then use the information given to answer the question below.

You can view the text of the audio file to read while you are listening.

Hint C.1

I can't hear anything


In which city was Mastering first used?

ANSWER:

Cambridge, Massachusetts

Indianapolis, Indiana

Toledo, Ohio

Phoenix, Arizona

I don't hear anything.


Part D Videos

Click on the arrow to play the video.

Hint D.1

I can't see the video


What is shown in the video? If you can't see the video use the hints for help.

ANSWER: details about how to use the captions in videos in Mastering details about how Mastering Assignments are graded

I don't hear/see anything.

details about how to use the hints to improve your score in Mastering Assignments


This section is a math diagnostic quiz, which will give you (and your instructors) a clearer picture of which mathematical techniques you have (or haven't) mastered. Don't be afraid! If you don't know how to do some of these things, we'll teach you how to tackle them. We will NOT base any opinion of your intelligence on how well (or poorly) you do on this diagnostic test.

Math Skills: Diagnostic Quiz

This quiz is designed to check your basic math skills. After you complete it, you should be able to tell which skills you have a good grasp of and which ones you need to review. You can review the skills on your own by watching the Math Skills videos in the Study Area, or by doing instructor-assigned Math Skills tutorials.

Part A Working with fractions

ANSWER:


Part B Working with fractions

ANSWER:


Part C Working with fractions

ANSWER:

0.375

38%

3.8%

0.38

0.25


Part D Powers and roots

ANSWER:


25

3

Part E Powers and roots

is between _____.

ANSWER:

2 and 3

1 and 2

5 and 8

3 and 4

0 and 1


Part F Powers and roots

ANSWER:


Part G

ANSWER:

Powers of 10

10.0000001

0.0000001

0.00000001

10,000,000


Part H Powers of 10

ANSWER:


Part I Powers of 10

ANSWER:

0.00001

100,000.1

10,000

99,990

1,000,000


Part J Scientific notation

In scientific notation,

ANSWER:


Part K Scientific notation

ANSWER:


Part L Scientific notation

ANSWER:


Part M Working with units

Mathematically, what is the correct way to write a speed of 100 meters per second?

ANSWER:

100


100

Part N Working with units

There are 3 feet in 1 yard. Therefore, 1 square yard is equivalent to _____.

ANSWER:

3

9

27


9

Part O Working with units

There are 1000 meters in 1 kilometer. The speed of light is 300,000 kilometers per second. Which statement below correctly converts the speed of light to units of meters per second?

ANSWER:


Part P Metric units

What is the mass of a typical adult?

ANSWER:

75 kilograms

75 grams per cubic centimeter

75 grams

75 liters

75 square meters


Part Q Metric units

The width of your thumb is about _____.

ANSWER:

2 meters

2 centimeters

2 milligrams

2 millimeters

2 grams


Part R Metric units

One kilometer is equivalent to how many micrometers?

ANSWER:


Part S Problem solving with units

Two days are equivalent to _____ seconds. (Assume exactly 24 hours in one day.)

ANSWER:

7200

86,400

43,200

2880


172,800

Part T Problem solving with units

You drop a rock and it accelerates with the acceleration of gravity, 9.8

ANSWER:

. How fast will it be going after 2 seconds?


Part U Precision and significant digits

A scale that can be read to the nearest pound shows your weight as 63 kilograms. You then write down that you weigh "63.00 kilograms."

Your statement is __________.

ANSWER: a better way to state your weight, because you've improved on the precision of the scale valid, because 63 and 63.00 are the same thing inaccurate, because it is not close to your true weight misleading, because it implies that you know your weight to greater precision than you actually do


Part V Precision and significant digits

How many significant digits are in the number 14,050.010?

ANSWER:

4

8

5 Answer not displayed

3

7

Part W Precision and significant digits

You travel at a speed of about 81 kilometers per hour for about 2.0 hours. Stated with the appropriate precision, you have driven _____ kilometers.

ANSWER:

162.0

162

160

162.00


Part X Problem-solving practice

Consider the types of units that go with the following equations. Which statement is valid?

ANSWER:


Part Y Problem-solving practice

The frequency of a photon of light is related to its wavelength by the following formula: where is the speed of light.

What is the frequency of a photon with a wavelength of

ANSWER:

meter?


The remaining problems in this assignment ARE for credit. Harder questions are worth more points than easier questions. There are no time limits or penalties for using hints on any of these problems.

Ranking Task: Astronomical Distances and Light-Travel Time

Learning Goal: To understand how astronomical distances relate to light-travel times and to how objects have aged since their light left on its way to

Earth.

Part A

Shown here are astronomical objects located at different distances from Earth. Rank the objects based on their distances from Earth, from farthest to nearest.

Hint A.1

Hint A.2

Hint A.3

Hint A.4

Hint A.5

ANSWER:

What is Alpha Centauri?


What is the Orion Nebula?


How big is the Milky Way Galaxy?


How far away is the Andromeda Galaxy?


How far away is the center of the Milky Way Galaxy?



Part B

Consider again the objects you ranked by distance in Part A. Suppose each object emitted a burst of light right now . Rank the objects from left to right based on the amount of time it would take this light to reach Earth, from longest time to shortest time.

Hint B.1

How long does it take light to travel great distances?


ANSWER:


Part C

Look once more at the objects you ranked in Parts A and B. This time, rank the objects from left to right based on how much they have aged since they emitted the light we see today, from greatest to least.

Hint C.1

How do you determine how much an object has aged since its light left?


Hint C.2

ANSWER:

When did light leave a star 10 light-years away?



Process of Science: Observations vs. Explanations

Learning Goal: To understand the scientific distinction between what we actually observe and ways in which we attempt to explain what we observe.

Introduction . In science, it is important to be able to distinguish between an observation (something we actually see or measure) and an explanation

(essentially a hypothesis that seeks to explain what we observe). This activity will help you understand this distinction, first with everyday ideas and then with astronomical ideas.

Part A

Consider each of the following statements that you might hear in everyday life. Classify each statement as either an observation or an explanation .

Hint A.1

Definition of an observation


Hint A.2

Hint A.3

Definition of an explanation


Does your appointment calendar explain where you are?


ANSWER:

Part B


Problem 1.5

Part A

How fast does light travel? What is a light-year ?

Essay answers are limited to about 500 words (3800 characters maximum, including spaces).

ANSWER:


Problem 1.6

Part A

Explain the statement " The farther away we look in distance, the further back we look in time.

"


ANSWER:


Problem 1.7

Part A

What do we mean by the observable universe ? Is it the same thing as the entire universe?



ANSWER:


Problem 1.12

Part A

What is the shape of the Milky Way Galaxy? Describe our solar system’s location and motion.


ANSWER:


Problem 1.13

Part A

Distinguish between our galaxy's disk and halo .

ANSWER:


Part B


Problem 1.25

Choose the best answer.

Part A

Which of the following correctly lists our "cosmic address" from small to large?

ANSWER:

Earth, solar system, Milky Way Galaxy, Local Group, Local Supercluster, universe;

Earth, solar system, Local Group, Local Supercluster, Milky Way Galaxy, universe;

Earth, Milky Way Galaxy, solar system, Local Group, Local Supercluster, universe.


Problem 1.29


Part A

The star Betelgeuse is about 425 light-years away. If it explodes tonight:

ANSWER:

We'll know because it will be brighter than the full Moon in the sky.

We'll know because debris from the explosion will rain down on us from space.

We won't know about it until 425 years from now.


Problem 1.33


Part A

An astronomical unit is:

ANSWER: any planet's average distance from the Sun.

Earth's average distance from the Sun.

any large astronomical distance.


Problem 1.44

Just as a light-year is the distance that light can travel in 1 year, we define a light-second as the distance that light can travel in 1 second, a light-minute as the distance that light can travel in 1 minute, and so on. Calculate the distance in both kilometers and miles represented by each of the following:

Part A

1 light-second in kilometers

Express your answer using three significant figures.

ANSWER:

=


Part B

1 light-second in miles


ANSWER:

=


Part C

1 light-minute in kilometers


ANSWER:

=


Part D

1 light-minute in miles


ANSWER:

=


Part E

1 light-hour in kilometers


ANSWER:

=


Part F

1 light-hour in miles


ANSWER:

= Answer not displayed

Part G

1 light-day in kilometers


ANSWER:

=


Part H

1 light-day in miles


ANSWER:

=


Problem 1.45

Part A

How long does it take light to travel from the Moon to Earth?

ANSWER:

=


Part B

How long does it take light to travel from the Sun to Earth?

ANSWER:

=


Problem S1.8

Part A

What are declination and right ascension ? How are these celestial coordinates similar to latitude and longitude on Earth? How are they different?


ANSWER:


Problem S1.30


Part A

A star's path through your sky depends on your latitude and the star's:

ANSWER: declination.

right ascension.

both declination and right ascension.


Problem S1.32


Part A

At the North Pole on the summer solstice, the Sun:

ANSWER: remains stationary in the sky.

reaches the zenith at noon.

circles the horizon at altitude .



Part A

The time from one spring equinox to the next is the:

Problem S1.25

ANSWER: sidereal day.

tropical year.

synodic month.


Score Summary:

Your score on this assignment is 0%.

You received 0 out of a possible total of 36 points.

Introduction to MasteringAstronomy + Ch 1

Introduction to MasteringAstronomy + Ch 1

Due: 9:00am on Tuesday, September 27, 2011

Welcome to Mastering Questions

Introduction to Numeric Answers

Introduction to Significant Figures

Introduction to Multimedia in Mastering

Math Skills: Diagnostic Quiz

Ranking Task: Astronomical Distances and Light-Travel Time

Process of Science: Observations vs. Explanations

Problem 1.5

Problem 1.6

Problem 1.7

Problem 1.12

Problem 1.13

Problem 1.25

Problem 1.29

Problem 1.33

Problem 1.44

Problem 1.45

Problem S1.8

Problem S1.30

Problem S1.32

Problem S1.25

Score Summary:

Related documents

Products

Support

Introduction to MasteringAstronomy + Ch 1