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Is there a massive black hole at the center of our galaxy, the Milky

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Re: Is there a massive black hole at the center of our galaxy, the Milky [#permalink] New post   24 Jan 2020, 04:02
gmatt1476 wrote:
gmatt1476 wrote:
⠀⠀⠀⠀⠀⠀⠀⠀This passage is excerpted from material published
in 1997.
⠀⠀⠀⠀⠀⠀⠀⠀Is there a massive black hole at the center of our
⠀⠀⠀ galaxy, the Milky Way? The evidence is inconclusive.
(5)  Just as the Sun's mass can be determined, given
⠀⠀⠀ knowledge of other variables, by the velocity at
⠀⠀⠀ which its planets orbit, the mass at the center of the
⠀⠀⠀ Milky Way can be revealed by the velocities of stars
⠀⠀⠀ and gas orbiting the galactic center. This dynamical
(10)  evidence, based on recently confirmed assumptions
⠀⠀⠀ about the stars' velocities, argues for an extremely
⠀⠀⠀ compact object with a mass two to three million
⠀⠀⠀ times the mass of our Sun. Although according to
⠀⠀⠀ current theory this makes the mass at the center
(15)  of the galaxy too dense to be anything but a black
⠀⠀⠀ hole, the relative lack of energy radiating from the
⠀⠀⠀ galactic center presents a serious problem. A black
⠀⠀⠀ hole's gravity attracts surrounding matter, which
⠀⠀⠀ swirls around the black hole, emitting some energy
(20)  as it is engulfed. Scientists believe that the amount of
⠀⠀⠀ energy that escapes the black hole should be about
⠀⠀⠀ 10 percent of the matter's rest energy (the energy
⠀⠀⠀ equivalent of its mass according to the equation
⠀⠀⠀ E=mc^2). But when the energy coming from the
(25)  galactic center is compared to widely held predictions
⠀⠀⠀ based on how much matter should be falling into a
⠀⠀⠀ theoretical central black hole, there is a discrepancy
⠀⠀⠀ by a factor of a few thousand.


1. The primary purpose of the passage is to

A. present several theories that could account for a particular phenomenon
B. argue that a certain question needs to be reframed in light of new evidence
C. resolve an apparent inconsistency between two lines of evidence
D. explain why a certain issue remains unresolved
E. present evidence that calls into question certain assumptions of a current theory

RC60500.01-10



2. According to the passage, the dynamical evidence referred to in lines 9–10 supports which of the following?

A. Recent assumptions about the velocities of stars
B. Widely held predictions about the amount of matter a black hole will engulf
C. The existence of an extremely dense object at the center of the Milky Way
D. The contention that too much energy is coming from the mass at the Milky Way's galactic center for that mass to be a black hole
E. The conclusion that a compact object of two to three million times the mass of our Sun is too dense to be anything but a black hole

RC60500.01-20



3. The “serious problem” referred to in line 17 could be solved if which of the following were true?

A. Current assumptions about how much matter a black hole would engulf proved to be several thousand times too high.
B. Current assumptions about how much matter a black hole would engulf proved to be a few thousand times too low.
C. The object at the center of the Milky Way turned out to be far more dense than it is currently estimated to be.
D. The object at the center of the Milky Way turned out to be far more massive than it is currently estimated to be.
E. Matter being engulfed by a black hole radiated far more energy than is currently assumed.

RC60500.01-30



4. The “widely held predictions” mentioned in line 25 are predictions about the

A. compactness of objects whose mass is millions of times the mass of our Sun
B. velocities of stars orbiting the galactic center
C. amount of matter swirling around the object at the center of the Milky Way
D. amount of matter falling into a theoretical central black hole
E. amount of energy that should be coming from a black hole at the center of the Milky Way

RC60500.01-40



Official Explanation

RC60500.01-30

3. The “serious problem” referred to in line 17 could be solved if which of the following were true?

A. Current assumptions about how much matter a black hole would engulf proved to be several thousand times too high.
B. Current assumptions about how much matter a black hole would engulf proved to be a few thousand times too low.
C. The object at the center of the Milky Way turned out to be far more dense than it is currently estimated to be.
D. The object at the center of the Milky Way turned out to be far more massive than it is currently estimated to be.
E. Matter being engulfed by a black hole radiated far more energy than is currently assumed.

Application

Which one of the five options would, if true, indicate a possible solution to the serious problem referred to? The serious problem is said to arise from the relative lack of energy radiating from the galactic center compared with the expected value if a matter-engulfing black hole were truly at the center of the Milky Way.

According to the passage, the radiated energy turned out to be a few thousand times less than had been expected, on theoretical grounds, to radiate from mass engulfed by the hypothetical black hole. However, if it were discovered that the matter engulfed were several thousand times less than previously estimated, the relatively low level of radiated energy observed would no longer seem at odds with the existence of the hypothesized black hole.

A. Correct. Reviewing the assumptions underlying the widely held predictions could lead to revised predictions that harmonize with the observational evidence regarding radiated energy from the galaxy's center.

B. The passage states that the assumed quantity of engulfed matter already seems to be radiating too little; this answer choice would actually make the “serious problem” in the passage worse. That is, assuming that there is actually more engulfed matter with such a small amount of radiation would simply worsen the problem.

C. The passage does not specify what impact a greater-than-estimated density would have on the quantity of energy that is radiated. That is, even if greater mass would change predictions, greater density may not do so.

D. If the object were more massive, then presumably the matter engulfed by this hypothetical more massive black hole would radiate a quantity of energy even greater than the observed quantity. This again would simply make the “serious problem” worse.

E. Given that not enough radiated energy is currently being observed, finding that the matter being engulfed radiates even more energy than expected would make the “serious problem” significantly worse. That is, the relatively low quantity of radiated energy observed would fall even farther short of the quantity expected.

The correct answer is A.


HiGMATNinja, VeritasKarishma MartyTargetTestPrep

Statement from the passage:
But when the energy coming from the galactic center is compared to widely held predictions based on how much matter should be falling into a theoretical central black hole, there is a discrepancy by a factor of a few thousand

According to the passage, there is a discrepancy of a factor of few thousands in the light emitted by the center of the galaxy.

According to official explanation, the discrepancy has been interpreted as a shortage of energy.

Can't discrepancy refer to excess of energy too?

Thank you.
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Re: Is there a massive black hole at the center of our galaxy, the Milky [#permalink] New post   28 Jan 2020, 10:01
Ques 3

Scientists believe according to E=mc^2......... they say the energy is 10% of matter's energy
and the energy is less about 1000 times than the energy predicted, on the basis of how much those blackholes engulfed. As given, that low level of energy is a problem. How can we increase that energy to solve the problem?

'More the matter, more the energy' as the passage states.

Scientists believe that the amount of
⠀⠀⠀ energy that escapes the black hole should be about
⠀⠀⠀ 10 percent of the matter's rest energy (the energy
⠀⠀⠀ equivalent of its mass according to the equation
⠀⠀⠀ E=mc^2).




So, to increase the energy by 1000 times, we need to give it the matter 1000 times greater.
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Re: Is there a massive black hole at the center of our galaxy, the Milky [#permalink] New post   13 May 2020, 05:18
GMATNinja
Hi,
I have a question regarding Q3 option D, if the object is much more massive, it could mean it's not a black hole and that clears our problem right?
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Re: Is there a massive black hole at the center of our galaxy, the Milky [#permalink] New post   07 Aug 2020, 14:21
Hi experts, In question 3: The ???serious problem??? referred to in line 17 could be solved if which of the following were true?

A. Current assumptions about how much matter a black hole would engulf proved to be several thousand times too high.

Isn't this choice incorrect because of the use of the word 'SEVERAL'? Discrepancy is by a factor of few thousand so if we have overestimated the mass by SEVERAL thousand times more, the discrepancy would still exist but now the energy maybe higher than expected?
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Re: Is there a massive black hole at the center of our galaxy, the Milky [#permalink] New post   17 Oct 2020, 11:38
VeritasKarishma GMATNinja

Although according to
⠀⠀⠀ current theory this makes the mass at the center
  of the galaxy too dense to be anything but a black
⠀⠀⠀ hole.
PLease explain question 2 why option E is wrong and C is correct and also explain what role does above two contrasting words play.
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Is there a massive black hole at the center of our galaxy, the Milky [#permalink] New post   30 Oct 2020, 08:12
Quote:
3. The “serious problem” referred to in line 17 could be solved if which of the following were true?

A. Current assumptions about how much matter a black hole would engulf proved to be several thousand times too high.
B. Current assumptions about how much matter a black hole would engulf proved to be a few thousand times too low.
C. The object at the center of the Milky Way turned out to be far more dense than it is currently estimated to be.
D. The object at the center of the Milky Way turned out to be far more massive than it is currently estimated to be.
E. Matter being engulfed by a black hole radiated far more energy than is currently assumed.

I too marked B on question 3, but the catch here is to read the option carefully.

1. We know that the current amount of energy emitted is way to low as compared to the scientist's assumption
2. In other words if the scientist's assumption is that \(x\) energy should be emitted then in reality the center of the Milky way is only emitting \(x-2\)
3. This question asks us to bridge the gap between \(x-2\) and \(x\)

If the scientist's were to re-evaluate their assumptions and revise them to \(x-2\) from \(x\) then it would be in line with the actual value of \(x-2\)
Now, read the non-stroked portion of option A:

A. Current assumptions about how much matter a black hole would engulf proved to be several thousand times too high.

And there's the answer - if the current assumption proved to be higher then what that means is that in reality it (the amount of energy emitted) is way lower. And then that solves the problem. Hurray! :cool:
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Re: Is there a massive black hole at the center of our galaxy, the Milky [#permalink] New post   01 Nov 2020, 23:51
GMATNinja wrote:
Lots of questions on #3! nick1816 and RK007 have it exactly right -- but I'll explain in a bit more depth in case that is helpful to anyone :)

First, let's look at the ASSUMPTION made by scientists: "Scientists believe that the amount of energy that escapes the black hole should be about 10 percent of the matter's rest energy."

Now let's look at the ACTUAL amount of energy escaping the black hole: "the relative lack of energy radiating from the galactic center presents a serious problem... compared to widely held predictions based on how much matter should be falling into a theoretical central black hole, there is a discrepancy by a factor of a few thousand."

So, the ACTUAL amount of energy escaping the black hole is significantly lower than the amount that scientists believe should be escaping based on their ASSUMPTION.

Stated another way, the amount of energy that scientists ASSUME should be escaping from the black hole is much higher than the ACTUAL amount of energy escaping the black hole.

Question #3 asks us to solve this problem.
Quote:
A. Current assumptions about how much matter a black hole would engulf proved to be several thousand times too high.

Okay, so according to (A) the scientists' current ASSUMPTION is way too high. What happens if we modify the current assumption to be thousands of times lower than it currently is, as suggested by (A)?

This totally fixes our problem -- the current assumption is much higher than the actual value. An assumption of a much lower amount of energy escaping the black hole would match the actual observation.

(A) is the correct answer.


GMATNinja, GMATNinjaTwo, VeritasKarishma, AnthonyRitz, CJAnish, MartyTargetTestPrep,AndrewN,VeritasPrepBrian
dear experts,
what makes me confused is I did catch which is actual energy, what is assumed energy.

one said is according to E=mc^2, one said is prediction.

for me, it is theoretical energy if according to E=mc^2, another is prediction. neither is an actual energy.

did I miss something ?

genuinely need your help.

thanks in advance
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Re: Is there a massive black hole at the center of our galaxy, the Milky [#permalink] New post   09 Nov 2020, 17:28
Passage Map:
- We can't say with certainty that there is a massive black hole at the center of our galaxy, the Milky Way.
- The mass can be determined by the velocities of stars and gas orbiting
- Based on this information, there should be an extremely compact object
- Lack of energy radiating from center is an issue -- there should be more energy radiating.


1. The primary purpose of the passage is to

A. present several theories that could account for a particular phenomenon
B. argue that a certain question needs to be reframed in light of new evidence
C. resolve an apparent inconsistency between two lines of evidence
D. explain why a certain issue remains unresolved
E. present evidence that calls into question certain assumptions of a current theory

Quote:
Is there a massive black hole at the center of our galaxy, the Milky Way? The evidence is inconclusive.


2. According to the passage, the dynamical evidence referred to in lines 9–10 supports which of the following?

A. Recent assumptions about the velocities of stars
B. Widely held predictions about the amount of matter a black hole will engulf
C. The existence of an extremely dense object at the center of the Milky Way
D. The contention that too much energy is coming from the mass at the Milky Way's galactic center for that mass to be a black hole
E. The conclusion that a compact object of two to three million times the mass of our Sun is too dense to be anything but a black hole

Quote:
This dynamical evidence, based on recently confirmed assumptions about the stars’ velocities, argues for an extremely compact object with a mass two to three million times the mass of our Sun. Although according to current theory this makes the mass at the center of the galaxy too dense to be anything but a black hole, the relative lack of energy radiating from the galactic center presents a serious problem.


3. The “serious problem” referred to in line 17 could be solved if which of the following were true?

A. Current assumptions about how much matter a black hole would engulf proved to be several thousand times too high.
B. Current assumptions about how much matter a black hole would engulf proved to be a few thousand times too low.
C. The object at the center of the Milky Way turned out to be far more dense than it is currently estimated to be.
D. The object at the center of the Milky Way turned out to be far more massive than it is currently estimated to be.
E. Matter being engulfed by a black hole radiated far more energy than is currently assumed.

Current assumptions right now are too low; if assumptions proved to be too high this issue would be solved.

4. The “widely held predictions” mentioned in line 25 are predictions about the

A. compactness of objects whose mass is millions of times the mass of our Sun
B. velocities of stars orbiting the galactic center
C. amount of matter swirling around the object at the center of the Milky Way
D. amount of matter falling into a theoretical central black hole
E. amount of energy that should be coming from a black hole at the center of the Milky Way

Quote:
But when the energy coming from the galactic center is compared to widely held predictions based on how much matter should be falling into a theoretical central black hole, there is a discrepancy by a factor of a few thousand.
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Re: Is there a massive black hole at the center of our galaxy, the Milky [#permalink] New post   20 Nov 2020, 04:35
3. The “serious problem” referred to in line 17 could be solved if which of the following were true?

A. Current assumptions about how much matter a black hole would engulf proved to be several thousand times too high.
B. Current assumptions about how much matter a black hole would engulf proved to be a few thousand times too low.
C. The object at the center of the Milky Way turned out to be far more dense than it is currently estimated to be.
D. The object at the center of the Milky Way turned out to be far more massive than it is currently estimated to be.
E. Matter being engulfed by a black hole radiated far more energy than is currently assumed.

Current assumptions proved to be too high.
How does this work.
From the context to resolve the discrepancy we know less matter than anticipated should be falling in to the black hole.

The current assumption is that more matter is falling into the black hole and that is why we have the discrepancy.

In order to to resolve this the current assumption must be proven wrong.

So the assumption/estimation proved to be quite high is conveyed by A. Actually it is way low.
and the opposite is conveyed by B.
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Re: Is there a massive black hole at the center of our galaxy, the Milky [#permalink] New post   24 Nov 2020, 14:17
hello,

In q3 we are given that the radiation differs by a factor of 1000. How do we come to the conclusion that the radiation is lacking by 1000?
Cant it increase by 1000?
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Is there a massive black hole at the center of our galaxy, the Milky [#permalink] New post   25 Nov 2020, 10:49
Milind39 wrote:
hello,

In q3 we are given that the radiation differs by a factor of 1000. How do we come to the conclusion that the radiation is lacking by 1000?
Cant it increase by 1000?


neetib wrote:
Please explain ques 3



Hi Milind39, neetib

Please refer the below reply by expert for Question 3:
https://gmatclub.com/forum/is-there-a-massive-black-hole-at-the-center-of-our-galaxy-the-milky-306222-20.html#p2396960


Let me know if you still have doubts.
Thanks.
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Re: Is there a massive black hole at the center of our galaxy, the Milky [#permalink] New post   29 Nov 2020, 10:52
Can anyone help with question # 3. Why is E not the correct answer. Thank you!
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Re: Is there a massive black hole at the center of our galaxy, the Milky [#permalink] New post   30 Nov 2020, 08:55
Niha01 wrote:
Can anyone help with question # 3. Why is E not the correct answer. Thank you!



Hi Niha01,

Please refer the below reply by expert GMAT Ninja for Question 3:
https://gmatclub.com/forum/is-there-a-massive-black-hole-at-the-center-of-our-galaxy-the-milky-306222-20.html#p2396960




Let me know if you still have doubts.
Thanks.
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Re: Is there a massive black hole at the center of our galaxy, the Milky [#permalink] New post   04 Dec 2020, 22:18
4/4 in 6 mins, not a terrible passage imo
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Re: Is there a massive black hole at the center of our galaxy, the Milky [#permalink] New post   09 Apr 2021, 03:45
Expert Reply
HansJK wrote:
Would be really grateful if someone could explain why 4d is wrong



4. The “widely held predictions” mentioned in line 25 are predictions about the

A. compactness of objects whose mass is millions of times the mass of our Sun
B. velocities of stars orbiting the galactic center
C. amount of matter swirling around the object at the center of the Milky Way
D. amount of matter falling into a theoretical central black hole
E. amount of energy that should be coming from a black hole at the center of the Milky Way



Scientists believe that the amount of
⠀⠀⠀ energy that escapes the black hole should be about
⠀⠀⠀ 10 percent of the matter's rest energy (the energy
⠀⠀⠀ equivalent of its mass according to the equation
⠀⠀⠀ E=mc^2). But when the energy coming from the
(25)  galactic center is compared to widely held predictions
⠀⠀⠀ based on how much matter should be falling into a
⠀⠀⠀ theoretical central black hole, there is a discrepancy
⠀⠀⠀ by a factor of a few thousand.


We are comparing energy coming from the centre with widely held predictions.

Widely held predictions on what? On how much energy should come from the centre based on how much matter should be falling into a central black home.

What do we find? We find that there is a discrepancy by a factor of a few 1000.

The actual energy coming from the centre can be compared with predicted amount of energy only. Only those numbers will be comparable.
How is the prediction made? Based on how much matter should fall into a central black hole.
The idea is that if the centre is a black hole, X amount of matter will fall into it and that will make the centre emit Y amount of energy. When the actual energy being emitted is measured, we find that there is a discrepancy by a factor of a few 1000. So then is it a black hole? We don't know.

Hence (E) is correct.
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Is there a massive black hole at the center of our galaxy, the Milky [#permalink] New post   14 Jun 2021, 02:57
VeritasKarishma


I am still confused between answers B and C in the following question.

2. According to the passage, the dynamical evidence referred to in lines 9–10 supports which of the following?

A. Recent assumptions about the velocities of stars
B. Widely held predictions about the amount of matter a black hole will engulf
C. The existence of an extremely dense object at the center of the Milky Way
D. The contention that too much energy is coming from the mass at the Milky Way's galactic center for that mass to be a black hole
E. The conclusion that a compact object of two to three million times the mass of our Sun is too dense to be anything but a black hole

the passage mentions the following
"This dynamical evidence, based on recently confirmed assumptions about the stars' velocities, argues for an extremely compact object with a mass two to three million times the mass of our Sun. Although according to current theory this makes the mass at the center of the galaxy too dense to be anything but a black hole"

the underlined portion of the passage mentions the presence of an extremely dense object, reading the second sentence we understand that the dense object referred to previously is at the center of the galaxy ( Milky Way).

The bleu portion of the passage states that the theory mentioned previously supports the assertion that the dense object is too dense to be anything but a back hole. This supports answer E. But some people argue in the forum that "the lack of Energy" mentioned in the passage undermines the conclusion supported previously as a result answer E is wrong. however one can argue that the question is focused on the function of the word "the dynamical evidence" which clearly supports the conclusion mentioned in answer E.

Thank you
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Re: Is there a massive black hole at the center of our galaxy, the Milky [#permalink] New post   18 Jun 2021, 02:06
Hi GMATNinja and VeritasKarishma,
Can you please explain the meaning of phrase "anything but a black hole".
I inferred it as it could be anything but not black hole, which is different from your reasoning.
Could you please explain the same. Thanks
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Re: Is there a massive black hole at the center of our galaxy, the Milky [#permalink] New post   20 Jan 2022, 07:24
KarishmaB wrote:
HansJK wrote:
Would be really grateful if someone could explain why 4d is wrong



4. The “widely held predictions” mentioned in line 25 are predictions about the

A. compactness of objects whose mass is millions of times the mass of our Sun
B. velocities of stars orbiting the galactic center
C. amount of matter swirling around the object at the center of the Milky Way
D. amount of matter falling into a theoretical central black hole
E. amount of energy that should be coming from a black hole at the center of the Milky Way



Scientists believe that the amount of
⠀⠀⠀ energy that escapes the black hole should be about
⠀⠀⠀ 10 percent of the matter's rest energy (the energy
⠀⠀⠀ equivalent of its mass according to the equation
⠀⠀⠀ E=mc^2). But when the energy coming from the
(25)  galactic center is compared to widely held predictions
⠀⠀⠀ based on how much matter should be falling into a
⠀⠀⠀ theoretical central black hole, there is a discrepancy
⠀⠀⠀ by a factor of a few thousand.


We are comparing energy coming from the centre with widely held predictions.

Widely held predictions on what? On how much energy should come from the centre based on how much matter should be falling into a central black home.

What do we find? We find that there is a discrepancy by a factor of a few 1000.

The actual energy coming from the centre can be compared with predicted amount of energy only. Only those numbers will be comparable.
How is the prediction made? Based on how much matter should fall into a central black hole.
The idea is that if the centre is a black hole, X amount of matter will fall into it and that will make the centre emit Y amount of energy. When the actual energy being emitted is measured, we find that there is a discrepancy by a factor of a few 1000. So then is it a black hole? We don't know.

Hence (E) is correct.



Hi KarishmaB
That meant if there are any choices that mentioned about "amount of energy", it will be correct?
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Re: Is there a massive black hole at the center of our galaxy, the Milky [#permalink] New post   20 Jan 2022, 21:10
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Teitsuya wrote:
KarishmaB wrote:
HansJK wrote:
Would be really grateful if someone could explain why 4d is wrong



4. The “widely held predictions” mentioned in line 25 are predictions about the

A. compactness of objects whose mass is millions of times the mass of our Sun
B. velocities of stars orbiting the galactic center
C. amount of matter swirling around the object at the center of the Milky Way
D. amount of matter falling into a theoretical central black hole
E. amount of energy that should be coming from a black hole at the center of the Milky Way



Scientists believe that the amount of
⠀⠀⠀ energy that escapes the black hole should be about
⠀⠀⠀ 10 percent of the matter's rest energy (the energy
⠀⠀⠀ equivalent of its mass according to the equation
⠀⠀⠀ E=mc^2). But when the energy coming from the
(25)  galactic center is compared to widely held predictions
⠀⠀⠀ based on how much matter should be falling into a
⠀⠀⠀ theoretical central black hole, there is a discrepancy
⠀⠀⠀ by a factor of a few thousand.


We are comparing energy coming from the centre with widely held predictions.

Widely held predictions on what? On how much energy should come from the centre based on how much matter should be falling into a central black home.

What do we find? We find that there is a discrepancy by a factor of a few 1000.

The actual energy coming from the centre can be compared with predicted amount of energy only. Only those numbers will be comparable.
How is the prediction made? Based on how much matter should fall into a central black hole.
The idea is that if the centre is a black hole, X amount of matter will fall into it and that will make the centre emit Y amount of energy. When the actual energy being emitted is measured, we find that there is a discrepancy by a factor of a few 1000. So then is it a black hole? We don't know.

Hence (E) is correct.



Hi KarishmaB
That meant if there are any choices that mentioned about "amount of energy", it will be correct?



Teitsuya - The option mentioning "amount of energy coming from the galactic center" will be correct, not say "amount of energy coming from the the solar system" etc.
This is so because we are comparing "actual amount of energy coming from galactic centre" with its predicted value.
Since only option (E) talks about amount of energy, we don't need to worry. We know it must mention the correct amount of energy since no other option can be correct.
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Re: Is there a massive black hole at the center of our galaxy, the Milky [#permalink] New post   17 Jun 2022, 00:01
shridhar786 wrote:
NoMatterWhat wrote:
UPS67 wrote:
I have issue with the explanation of Question 2.

As you mentioned "However, if it were discovered that the matter engulfed were several thousand times less than previously estimated, the relatively low level of radiated energy observed would no longer seem at odds with the existence of the hypothesized black hole."

A. Current assumptions about how much matter a black hole would engulf proved to be several thousand times too high.
B. Current assumptions about how much matter a black hole would engulf proved to be a few thousand times too low.

So option A is opposite and option B fits in.
Hence, could you please check the option and correct me if my understanding is wrong.



I m with you, I checked on Option B too.....Please someone help us out


I am with both of you
can anyone help us out with question number 3



Please note the usage of the word 'Proved'. There is a discrepancy between what was discovered and what was the widely held belief. If the widely held belief proved to be thousand times too high, the discrepancy would be resolved.

Take the example below:

Energy = 100
Energy emitted from the black hole = 10% * 100 = 10

Widely held belief of energy emitted from the black hold = 10,000

If the widely held belief was proved to be several thousand times too high, the new widely held belief of energy to be emitted = 10 (which is inline with the evidence)

Hence, ans is A. I had initially selected Ans B only to later realize that I had misread the answer choice.
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Re: Is there a massive black hole at the center of our galaxy, the Milky [#permalink]
17 Jun 2022, 00:01
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