GMAT Question of the Day - Daily to your Mailbox; hard ones only

 It is currently 16 Jul 2018, 13:28

GMAT Club Daily Prep

Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

Author Message
TAGS:

Hide Tags

Manager
Joined: 03 Jul 2012
Posts: 120
GMAT 1: 710 Q50 V36
GPA: 3.9
WE: Programming (Computer Software)

Show Tags

01 Sep 2012, 06:56
3
3
Question 1
00:00

Question Stats:

45% (02:31) correct 55% (01:47) wrong based on 150

HideShow timer Statistics

Question 2
00:00

Question Stats:

42% (01:11) correct 58% (01:09) wrong based on 139

HideShow timer Statistics

Radio galaxies and quasars--quasi-stellar radio sources--usually display two symmetric, radio-emitting lobes. These sources can stretch more than 10 million light years across--more than twenty times the visible extent of the typical host galaxy, and more than 100 million times the diameter of the Milky Way.
In 1971, Martin J. Rees suggested that hidden engines located within the nuclei of the parent galaxies generate the energy needed to power the giant radio lobes. He proposed that high-speed particles shooting along narrow channels could transport this energy. A few years later other investigators demonstrated that, in many sources, jet-like features do seem to connect a radio-bright core in the galaxy’s nucleus
with knots of radio emissions emanating from the outer extremities of the lobes. The nature of the engine that powers the processes in radio galaxies and quasars is still a mystery, but most astronomers think a massive rotating black hole lies behind all the commotion. Theorists commonly suppose that material spiraling toward a black hole becomes compressed and heated to a temperature of millions of degrees before it vanishes into the hole’s interior. The superheated particles circling the hole may be responsible for various exotic phenomena that occur in and around the centers of active galaxies, such as the formation of radio jets.
1. According to the passage, which one of the following is an accurate statement concerning radio-emitting lobes?
Their exact energy source remains a question for scientists.
They stretch more than 10 million light years across.
They are probably responsible for the formation of radio jets around the centers of active galaxies.
They are always symmetric in their orientation.

2. According to the passage, scientists' hypotheses about black holes and their part in radio-emissions would be best supported if which of the following were found to be true?
Some particles become greatly condensed and raised to high temperatures as they near the entrances to black holes.
Many exotic phenomena have been observed in and around the centers of active galaxies.
High-speed particles do, in fact, shoot along narrow channels and transport energy from quasars and radio galaxies to their lobes.
Particles inside black holes have been shown to reach temperatures of several million degrees.
Radio emissions of radio galaxies were found to have different wavelengths from those of quasars.

Manager
Joined: 03 Jul 2012
Posts: 120
GMAT 1: 710 Q50 V36
GPA: 3.9
WE: Programming (Computer Software)

Show Tags

04 Sep 2012, 10:17
Hey can any of the experts help me out here??
Board of Directors
Joined: 01 Sep 2010
Posts: 3428

Show Tags

05 Sep 2012, 09:53
3
It was a nice passage, I would say.

The important thing is to pay attention on what the passage says and what is asked by the questions.

Try to break al the answers one by one, go step by step ahead like me

Quote:
Radio galaxies and quasars--quasi-stellar radio sources--usually display two symmetric, radio-emitting lobes. These sources can stretch more than 10 million light years across--more than twenty times the visible extent of the typical host galaxy, and more than 100 million times the diameter of the Milky Way.
In 1971, Martin J. Rees suggested that hidden engines located within the nuclei of the parent galaxies generate the energy needed to power the giant radio lobes. He proposed that high-speed particles shooting along narrow channels could transport this energy. A few years later other investigators demonstrated that, in many sources, jet-like features do seem to connect a radio-bright core in the galaxy’s nucleus
with knots of radio emissions emanating from the outer extremities of the lobes
. The nature of the engine that powers the processes in radio galaxies and quasars is still a mystery, but most astronomers think a massive rotating black hole lies behind all the commotion. Theorists commonly suppose that material spiraling toward a black hole becomes compressed and heated to a temperature of millions of degrees before it vanishes into the hole’s interior. The superheated particles circling the hole may be responsible for various exotic phenomena that occur in and around the centers of active galaxies, such as the formation of radio jets.

For the first one is B because:

A) They are powered by superheated particles spiraling toward black holes. Is not true

B) Their exact energy source remains a question for scientists. TRUE the passage says " The nature of the engine that powers the processes in radio galaxies and quasars is still a mystery"

C) They stretch more than 10 million light years across. We already know

D) They are probably responsible for the formation of radio jets around the centers of active galaxies. The red part about jets imply that they go toward NOT around

E) They are always symmetric in their orientation. We have symmetric lobes but nothig is said about orientation.

The sesond one is A, same reasoning is applyed to find the correct answer:

A) Some particles become greatly condensed and raised to high temperatures as they near the entrances to black holes. from the passage "Theorists commonly suppose that material spiraling toward a black hole becomes compressed and heated to a temperature of millions of degrees before it vanishes into the hole’s interior"

B) Many exotic phenomena have been observed in and around the centers of active galaxies. is not the point

C) High-speed particles do, in fact, shoot along narrow channels and transport energy from quasars and radio galaxies to their lobes. from the passage "He proposed that high-speed particles shooting along narrow channels could transport this energy" not the word could instead of the word in the answer DO. this shift imply that can't be the correct answer : could is not TRUE. maybe yes or maybe no

D) Particles inside black holes have been shown to reach temperatures of several million degrees. Once again here the theorist SUPPOSE the heat not has observed it

E) adio emissions of radio galaxies were found to have different wavelengths from those of quasars. I didn't read wavelenght anywhere in the passage
_________________
Manager
Joined: 03 Jul 2012
Posts: 120
GMAT 1: 710 Q50 V36
GPA: 3.9
WE: Programming (Computer Software)

Show Tags

05 Sep 2012, 13:21
1
carcass wrote:
It was a nice passage, I would say.

The important thing is to pay attention on what the passage says and what is asked by the questions.

Try to break al the answers one by one, go step by step ahead like me

Quote:
Radio galaxies and quasars--quasi-stellar radio sources--usually display two symmetric, radio-emitting lobes. These sources can stretch more than 10 million light years across--more than twenty times the visible extent of the typical host galaxy, and more than 100 million times the diameter of the Milky Way.
In 1971, Martin J. Rees suggested that hidden engines located within the nuclei of the parent galaxies generate the energy needed to power the giant radio lobes. He proposed that high-speed particles shooting along narrow channels could transport this energy. A few years later other investigators demonstrated that, in many sources, jet-like features do seem to connect a radio-bright core in the galaxy’s nucleus
with knots of radio emissions emanating from the outer extremities of the lobes
. The nature of the engine that powers the processes in radio galaxies and quasars is still a mystery, but most astronomers think a massive rotating black hole lies behind all the commotion. Theorists commonly suppose that material spiraling toward a black hole becomes compressed and heated to a temperature of millions of degrees before it vanishes into the hole’s interior. The superheated particles circling the hole may be responsible for various exotic phenomena that occur in and around the centers of active galaxies, such as the formation of radio jets.

For the first one is B because:

A) They are powered by superheated particles spiraling toward black holes. Is not true

B) Their exact energy source remains a question for scientists. TRUE the passage says " The nature of the engine that powers the processes in radio galaxies and quasars is still a mystery"

C) They stretch more than 10 million light years across. We already know

D) They are probably responsible for the formation of radio jets around the centers of active galaxies. The red part about jets imply that they go toward NOT around

E) They are always symmetric in their orientation. We have symmetric lobes but nothig is said about orientation.

The sesond one is A, same reasoning is applyed to find the correct answer:

A) Some particles become greatly condensed and raised to high temperatures as they near the entrances to black holes. from the passage "Theorists commonly suppose that material spiraling toward a black hole becomes compressed and heated to a temperature of millions of degrees before it vanishes into the hole’s interior"

B) Many exotic phenomena have been observed in and around the centers of active galaxies. is not the point

C) High-speed particles do, in fact, shoot along narrow channels and transport energy from quasars and radio galaxies to their lobes. from the passage "He proposed that high-speed particles shooting along narrow channels could transport this energy" not the word could instead of the word in the answer DO. this shift imply that can't be the correct answer : could is not TRUE. maybe yes or maybe no

D) Particles inside black holes have been shown to reach temperatures of several million degrees. Once again here the theorist SUPPOSE the heat not has observed it

E) adio emissions of radio galaxies were found to have different wavelengths from those of quasars. I didn't read wavelenght anywhere in the passage

@carcass- Thanks Man!
Board of Directors
Joined: 01 Sep 2010
Posts: 3428

Show Tags

05 Sep 2012, 15:00
1
Kudos ?? :D
_________________
Manager
Joined: 05 Jan 2011
Posts: 56

Show Tags

20 Sep 2012, 21:19
@Carcass - could not get your idea behind Qs#2 .I chose -D for 2 .To me its like - if we get evidence of high temperature,we can confirm hypothesis?
VP
Joined: 02 Jul 2012
Posts: 1193
Location: India
Concentration: Strategy
GMAT 1: 740 Q49 V42
GPA: 3.8
WE: Engineering (Energy and Utilities)

Show Tags

07 Mar 2014, 04:32
Bumping for review and further discussion*.

*New project from GMAT Club!!! Check HERE
_________________

Did you find this post helpful?... Please let me know through the Kudos button.

Thanks To The Almighty - My GMAT Debrief

GMAT Reading Comprehension: 7 Most Common Passage Types

Current Student
Joined: 24 Feb 2014
Posts: 45
Concentration: Finance, Marketing
GMAT 1: 710 Q49 V38
GPA: 3.8
WE: Information Technology (Telecommunications)

Show Tags

26 Jun 2014, 05:53
Why cant option 'B' be the answer for 1st question.
The question is asking about an accurate statement and i think B is fair enough as it is explicitly mentioned in the passage.

Thanks,
Gaurav.
Manager
Joined: 20 Jul 2013
Posts: 58

Show Tags

28 Jun 2014, 09:39
vishu1414 wrote:
@Carcass - could not get your idea behind Qs#2 .I chose -D for 2 .To me its like - if we get evidence of high temperature,we can confirm hypothesis?

If we do have evidence that the temperature is indeed high --- how does that even prove that the theory is more likely to happen?
We don't need evidence to prove that the temperature is high ... We need to add something that will make the theory more likely (of what actually happens that leads to those high temperatures) possible.

Focus on the second-to-last sentence:
"Theorists commonly suppose that material spiraling toward a black hole becomes compressed and heated to a temperature of millions of degrees before it vanishes into the hole’s interior."

If choice A were true, then the theorists' supposition works. Without it, the theory can't even happen.
Choice D actually relies on Choice A, in order to be true. Choice D just says something that has no bearing on whether the theory can happen.

Choice A is what the theorists' theory completely relies on.
Retired Moderator
Joined: 19 Apr 2013
Posts: 654
Concentration: Strategy, Healthcare
Schools: Sloan '18 (A)
GMAT 1: 730 Q48 V41
GPA: 4

Show Tags

18 Mar 2015, 09:49
Did not get the first question.
_________________

If my post was helpful, press Kudos. If not, then just press Kudos !!!

Intern
Joined: 27 Jan 2015
Posts: 15
GMAT 1: 580 Q50 V19
WE: Corporate Finance (Consumer Products)

Show Tags

14 Apr 2015, 04:32
1
Ergenekon wrote:
Did not get the first question.

let me try the first question.
1. According to the passage, which one of the following is an accurate statement concerning radio-emitting lobes? So we need to find the statement that is considered accurate.
They are powered by superheated particles spiraling toward black holes. They are maybe powered by superheated particles...But according to the passage, this statement is only one of possible explanations. The underlying explanation is still unknown. So this is not accurate. This answer could be correct if "They are probaly powered by superheated particles spiraling toward black holes.
Their exact energy source remains a question for scientists. Correct! This is mentioned in the passage: The nature of the engine that powers the processes in radio galaxies and quasars is still a mystery.
They stretch more than 10 million light years across. Radio galaxies and quasars can stretch more than 10 million light years across; however, Wwe don't know whether their radio-emitting lobes can.
They are probably responsible for the formation of radio jets around the centers of active galaxies. The superheated particles circling the hole (not radio-emitting lobes) may be responsible for various exotic phenomena that occur in and around the centers of active galaxies, such as the formation of radio jets.
They are always symmetric in their orientation. We know that they are symmetric, but the way in which they are symmetric is unknown.

Hope it helps!
Intern
Joined: 04 Sep 2014
Posts: 49
Schools: CBS '18 (D)

Show Tags

10 May 2015, 04:55
I spent a chunk of time on the second question. My issue is that the correct answer choice is, with some tweaking, a direct lift of the relevant sentence from the passage, and I was thinking "the answer is too obvious so it must be wrong". I was hesitating between A and B - the other option were horrible - and figured that B depended on A, and therefore chose A.

Phew...
Intern
Joined: 04 Apr 2017
Posts: 18

Show Tags

31 Aug 2017, 01:40
For the first question :

A) They are powered by superheated particles spiraling toward black holes. - This is some astronomers' hypothesis which is not shown to be the accurate and final hypothesis and we can't take a side here. Not a correct one.

B) Their exact energy source remains a question for scientists. CORRECT - Lobes are powered by some engines in the center of the galaxy. The nature of the engine is not clear(even though a plausible hypothesis exists)

C) They stretch more than 10 million light years across. - Lobes "can usually stretch" for more than 10 million light years across NOT for sure

D) They are probably responsible for the formation of radio jets around the centers of active galaxies. - Radio jets connect the center/engine of the galaxy and emissions from outer extremes of the radio lobes

E) They are always symmetric in their orientation. - Always is incorrect here.

If you like the reasoning, please press "KUDOS"
Display posts from previous: Sort by

Events & Promotions

 Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.