Suppose we were in a spaceship in free fall, where objects are weightl

Dear GMATNinja, Experts

Could you please explain me question 5/Option B. Why option B is wrong. Passage 1 describes the steps to determine mass of an object in free fall. Passage 2 describes the steps to determine mass of stars in double star system. So, both passages talks about a scientific measurement by which unknown mass can be find out. I was able to eliminate all options except B and E. I chose B over E because I thought I know that passage1& 2 were trying to find out unknown Mass. Unknown Quantity in option E threw me off.

5. The primary purpose of the passage is to

A. analyze a natural phenomenon in terms of its behavior under special conditions
B. describe the steps by which a scientific measurement is carried out
C. point out the conditions under which a scientific procedure is most useful
D. contrast two different uses of a methodological approach in science
E. explain a method by which scientists determine an unknown quantity

'Scientists' is a generic term used for people studying any kind of science so it is acceptable.

The real difference lies in "describe the steps" and "explain a method".
Describe the steps would be "first, tie the object to a spring... then swing it really fast ..." etc. That is not what the passage does.
It tells you the method used to measure the masses. It explains you the concept and then how it is applicable to a star system. Hence (E) is better than (B).

VeritasKarishma,

I screened E as one of the final correct option but rejected it based on logic, option explains 'A method' however, the overall passage is about two different method, selecting ultimately option A although i was skeptical on word 'special conditions'. So, how can option E be correct?

Thanks!!

VeritasKarishma
Can you please explain why choice D is incorrect for question 5? Thank you

I am confused on choice E being correct because I understood the passage as explaining two methods, and I believe this is indicated when the author uses the wording an "analogous procedure" in passage two. The author also contrasts them when saying "analogous to the tension in the string" in the second paragraph.

The methodology proposed in the first paragraph involves a hypothetical technique for measuring a small solid object’s mass in space (by placing the object on a spring scale and swinging the scale in a circle at the end of a string).

The second paragraph does not discuss practical ways for using THAT hypothetical technique. In other words, the second paragraph does not analyze practical applications of the spring scale/small-solid-object method. Instead, the second paragraph describes a different technique that is analogous to the spring scale/small-solid-object method.

In other words, the second paragraph does not discuss (or analyze) the practical applications of the spring scale/small solid method. Instead, the second paragraph describes an analogous procedure. Furthermore, this analogous procedure is described but is not really analyzed.

Choice (A) is more accurate.

I hope that helps!

Suppose we were in a spaceship in free fall, where objects are weightless, and wanted to know a small solid object’s mass. We could not simply balance that object against another of known weight, as we would on Earth. The unknown mass could be determined, however, by placing the object on a spring scale and swinging the scale in a circle at the end of a string. The scale would measure the tension in the string, which would depend on both the speed of revolution and the mass of the object. The tension would be greater, the greater the mass or the greater the speed of revolution. From the measured tension and speed of whirling, we could determine the object’s mass.

Astronomers use an analogous procedure to “weigh” double-star systems. The speed with which the two stars in a double-star system circle one another depends on the gravitational force between them, which holds the system together. This attractive force, analogous to the tension in the string, is proportional to the stars’ combined mass, according to Newton’s law of gravitation. By observing the time required for the stars to circle each other (the period) and measuring the distance between them, we can deduce the restraining force, and hence the masses.

3. Which of the following best describes the relationship between the first and the second paragraph of the passage?

A The first paragraph provides an illustration useful for understanding a procedure described in the second paragraph.
B The first paragraph describes a hypothetical situation whose plausibility is tested in the second paragraph.
C The first paragraph evaluates the usefulness of a procedure whose application is described further in the second paragraph.
D The second paragraph provides evidence to support a claim made in the first paragraph.
E The second paragraph analyzes the practical implications of a methodology proposed in the first paragraph.

Suppose we were in a spaceship in free fall, where objects are weightless, and wanted to know a small solid object’s mass. We could not simply balance that object against another of known weight, as we would on Earth. The unknown mass could be determined, however, by placing the object on a spring scale and swinging the scale in a circle at the end of a string. The scale would measure the tension in the string, which would depend on both the speed of revolution and the mass of the object. The tension would be greater, the greater the mass or the greater the speed of revolution. From the measured tension and speed of whirling, we could determine the object’s mass.

Astronomers use an analogous procedure to “weigh” double-star systems. The speed with which the two stars in a double-star system circle one another depends on the gravitational force between them, which holds the system together. This attractive force, analogous to the tension in the string, is proportional to the stars’ combined mass, according to Newton’s law of gravitation. By observing the time required for the stars to circle each other (the period) and measuring the distance between them, we can deduce the restraining force, and hence the masses.

3. Which of the following best describes the relationship between the first and the second paragraph of the passage?

A The first paragraph provides an illustration useful for understanding a procedure described in the second paragraph.
B The first paragraph describes a hypothetical situation whose plausibility is tested in the second paragraph.
C The first paragraph evaluates the usefulness of a procedure whose application is described further in the second paragraph.
D The second paragraph provides evidence to support a claim made in the first paragraph.
E The second paragraph analyzes the practical implications of a methodology proposed in the first paragraph.

The unknown mass could be determined, however, by placing the object on a spring scale and swinging the scale in a circle at the end of a string. The scale would measure the tension in the string, which would depend on both the speed of revolution and the mass of the object. The tension would be greater, the greater the mass or the greater the speed of revolution. From the measured tension and speed of whirling, we could determine the object’s mass.

Thank you very much for the explanation.
In this question, the correct choice is A, but I picked the wrong choice (B).
In the passage, the word suppose means it is going to be hypothetical situation. For that reason, I've chosen B for the word hypothetical situation in the answer choice B.

I've crossed out choice A because of the word illustration. The word illustration is definitely connected with example, But the first para has no example at all, unfortunately. I can't figure out that whether any illustration in the first para?
Thanks__

B The first paragraph describes a hypothetical situation whose plausibility is tested in the second paragraph.

5. The primary purpose of the passage is to

A. analyze a natural phenomenon in terms of its behavior under special conditions
B. describe the steps by which a scientific measurement is carried out
C. point out the conditions under which a scientific procedure is most useful
D. contrast two different uses of a methodological approach in science
E. explain a method by which scientists determine an unknown quantity

'Scientists' is a generic term used for people studying any kind of science so it is acceptable.

The real difference lies in "describe the steps" and "explain a method".
Describe the steps would be "first, tie the object to a spring... then swing it really fast ..." etc. That is not what the passage does.
It tells you the method used to measure the masses. It explains you the concept and then how it is applicable to a star system. Hence (E) is better than (B).

In the above question my understanding for option E was that it is not stated what is the unknown quantity. So I rejected that choice since the word mass was not mentioned. The unknown quantity can be anything right?
So should we assume that since the passage talks about the mass so the unknown quantity it is referring is mass only?

KarishmaB GMATNinja GMATNinjaTwo Sajjad1994 bm2201
I have doubt in option B and E.

5. The primary purpose of the passage is to

A. analyze a natural phenomenon in terms of its behavior under special conditions
B. describe the steps by which a scientific measurement is carried out
C. point out the conditions under which a scientific procedure is most useful
D. contrast two different uses of a methodological approach in science
E. explain a method by which scientists determine an unknown quantity

However, as per my reasoning I am finding option B better than E because option E states 'explain a method' while we discussed 2 methods(one in passage 1 and other in passage 2) in the passage and additionally option mentions scientists whereas in the passage astronomers measure. If we look the 2 para steps are mentioned to determine mass with various steps being observe time, measure distance, deduce gravitational force, and finally determine mass. Please explain why is option B wrong.

I have taken this query here: https://gmatclub.com/forum/suppose-we-w ... l#p2544504

'Scientists' is a generic term used for people studying any kind of science so it is acceptable.

The real difference lies in "describe the steps" and "explain a method".
Describe the steps would be "first, tie the object to a spring... then swing it really fast ..." etc. That is not what the passage does.
It tells you the method used to measure the masses. It explains you the concept and then how it is applicable to a star system. Hence (E) is better than (B).

Note that we have discussed only one method. Tying to a string and whirling. We are applying that same method to the stars. There is an explanation of the method given to you and then how that method is applied to stars.

KarishmaB

Thank you for your helpful explanations, as always.

For question "it can be inferred from the passage that the two procedures described in the passage have which of the following in common?" Choice B is incorrect because the hypothetical example mentioned in paragraph 1 uses a physical device whereas there is no physical device to measure tension in the second paragraph, correct? Both measure tension (paragraph 2 says "this attractive force, analogous to the tension in the string"), correct?

Thank you again for all of your time and support / all your work on GMATCLUB