5. What does the professor imply about the asteroid belt?
A It is farther from the Sun than Uranus.
B Bode believed it was made up of small stars.
C It is located where people expected to find a planet.
D Ceres is the only one of the asteroids that can be seen without a telescope.
6. Listen again to part of the lecture by playing Track 8.
Then answer the question.
A B C D
Listening Section
Why does the professor say this?
To introduce an alternative application of Bode’s Law To give an example of what Bode’s Law cannot explain To describe the limitations of gravitational theory To contrast Bode’s Law with a real scientific law
Female Student Putting in a decimal?
Professor
Yes, I divided all those numbers by 10 by putting in a decimal point. Now I’m going to write the names of the planets under the numbers. Mercury . . . V enus . . . Ear th . . . Mars.
So, what do the numbers mean? Do you remember from the reading?
Male Student
Is it the distance of the planets from the Sun?
Professor
Right. In astronomical units—not perfect, but tantalizingly close. The value for Mars is off by . . . 6 or 7 percent or so. It’s . . . but it’s within 10 percent of the average distance to Mars from the Sun. But I kind of have to skip the one after Mars for now. Then Jupiter’s right there at 5-point something, and then Saturn is about 10 astronomical units from the Sun. Um, well, this pattern is known as Bode’s Law.
Um, it isn’t really a scientific law, not in the sense of predicting gravitation mathemati- cally or something, but it’s attempting a pattern in the spacing of the planets, and it was noticed by Bode hundreds of years ago. Well, you can imagine that there was some interest in why the 2.8 spot in the pattern was skipped, and um . . . but there wasn’t anything obvi- ous there, in the early telescopes. Then what happened in the late 1700s? The discovery of . . . ?
Female Student Another planet?
Professor
The next planet out, Uranus—after Saturn.
And look, Uranus fits in the next spot in the pattern pretty nicely, um, not perfectly, but close. And so then people got really excited about the validity of this thing and finding the missing object between Mars and Jupiter. And telescopes, remember, were getting better.
So people went to work on finding objects that would be at that missing distance from the Sun, and then in 1801, the object Ceres was discovered.
And Ceres was in the right place—the missing spot. Uh, but it was way too faint to be a planet. It looked like a little star. Uh, and because of its starlike appearance, um, it was called an “asteroid.” OK? Aster is Greek for “star,” as in astronomy. Um, and so, Ceres was the first and is the largest of what became many objects discovered at that same distance. Not just one thing, but all the objects found at that distance form the asteroid belt. So the asteroid belt is the most famous success of this Bode’s Law. That’s how the asteroid belt was discovered.
Listening Section
Answers and Explanations
1. D This is a Detail question. Although the entire passage is concerned with answering “What is Bode’s Law?” the professor specifically answers the ques- tion when he says, “it’s attempting a pattern in the spacing of the planets.”
The correct answer to this question is choice D.
2. B This is a Gist-Purpose question. Gist questions are not usually answered very explicitly in the passage, but in this case the professor addresses the purpose of the discussion twice. At one point he says, “Today I’m going to talk about how the asteroid belt was discovered,” and later he states, “That’s how the asteroid belt was discovered.” The correct answer to this question is choice B.
3. A This is an Understanding Organization question. The professor first dem- onstrates the pattern of numbers before explaining Bode’s Law and what the pattern means. The correct answer to this question is choice A.
4. A D This is a Detail question. Note that for this question there are two correct answers. The professor explains that “Uranus fits in the next spot in the pattern pretty nicely” and telescopes “were getting better . . . and then in 1801, the object Ceres was discovered.” Choices A and D are the correct answers. Advances in mathematics and the discovery of a new star are not mentioned by the professor.
5. C This is a Making Inferences question. Starting at the point in the passage where the professor says, “there was some interest in why the 2.8 spot in the pattern was skipped . . . there wasn’t anything obvious there,” it’s clear that what the astronomers were looking for was a planet. He later says, “Ceres was in the right place . . . but it was way too faint to be a planet.” The clear impli- cation is that astronomers were expecting to find a planet. The correct answer to the question is choice C.
6. D This replay question requires you to Understand the Function of What Is Said. The pattern the professor describes is called Bode’s Law. The professor is pointing out how Bode’s Law differs from other scientific laws. The correct answer to this question is choice D.
Listening Section
PRACTICE SET 5
Listening Section
Now listen to Track 9.
Listening Section
Questions
Directions: Mark your answer by filling in the oval or square next to your choice.
1. What aspect of Manila hemp fibers does the professor mainly describe in the lecture?
A Similarities between cotton fibers and Manila hemp fibers
B Various types of Manila hemp fibers
C The economic importance of Manila hemp fibers
D A use of Manila hemp fibers
2. What does the professor imply about the name “Manila hemp”?
A It is a commercial brand name.
B Part of the name is inappropriate.
C The name has recently changed.
D The name was first used in the 1940s.
3. Why does the professor mention the Golden Gate Bridge?
A To demonstrate a disadvantage of steel cables
B To give an example of the creative use of color
C To show that steel cables are able to resist salt water
D To give an example of a use of Manila hemp
4. According to the professor, what was the main reason that many ships used Manila hemp ropes instead of steel cables?
A Manila hemp was cheaper.
B Manila hemp was easier to produce.
C Manila hemp is more resistant to salt water.
D Manila hemp is lighter in weight.
5. According to the lecture, what are two ways to increase the strength of rope made from Manila hemp fibers?
Choose 2 answers.
A Coat the fibers with zinc-based paint
B Combine the fibers into bundles
C Soak bundles of fibers in salt water
D Twist bundles of fibers
6. Listen again to part of the lecture by playing Track 10.
Then answer the question.
Why does the professor mention going away for the weekend?
A To tell the class a joke
B To apologize for not completing some work
C To introduce the topic of the lecture
D To encourage students to ask about her trip