On the nights immediately following the mysterious Tunguska event, whi

Question

On the nights immediately following the mysterious Tunguska event, which destroyed a tract of Siberian wilderness in 1908, eyewitnesses reported seeing noctilucent clouds—brilliant night-visible clouds made up of ice particles that form rarely and only at very high altitudes. Recently, noctilucent clouds have been observed on the nights following launches of rockets that release large amounts of water vapor into the upper atmosphere. This shows that it was a comet impact and not the impact of an asteroid that caused the destruction in Siberia.

The argument depends on assuming which one of the following?

(A) Comets but not asteroids release large amounts of water vapor into the upper atmosphere when they collide with Earth.

(B) Noctilucent clouds are visible for many consecutive nights following the release of water vapor into the upper atmosphere.

(C) Comets collide with Earth more frequently than asteroids do.

(D) Eyewitnesses have reported seeing noctilucent clouds after asteroids have collided with Earth.

(E) The fact that noctilucent clouds are made of ice particles in the upper atmosphere was only recently discovered.

sanjitscorps18 · Answer

(A) Comets but not asteroids release large amounts of water vapor into the upper atmosphere when they collide with Earth.
 --> Correctly differentiates asteroids from comets with respect to the argument's discussion

(B) Noctilucent clouds are visible for many consecutive nights following the release of water vapor into the upper atmosphere.
--> Irrelevant. Already mentioned in the argument

(C) Comets collide with Earth more frequently than asteroids do.
--> Irrelevant. Not the topic of the argument

(D) Eyewitnesses have reported seeing noctilucent clouds after asteroids have collided with Earth.
--> Goes against the argument

(E) The fact that noctilucent clouds are made of ice particles in the upper atmosphere was only recently discovered.
--> Irrelevant to the topic at hand.

Option A

ITERM · Answer

was the rocket just a distraction to the assumption in the question? Smartly framed question if thats true

shessa · Answer

please provide official ans explanation

AbhishekP220108 · Answer

Hi  shessa  let me try to help

On the nights immediately following the mysterious Tunguska event, which destroyed a tract of Siberian wilderness in 1908, eyewitnesses reported seeing noctilucent clouds—brilliant night-visible clouds made up of ice particles that form rarely and only at very high altitudes. Recently, noctilucent clouds have been observed on the nights following launches of rockets that release large amounts of water vapor into the upper atmosphere. This shows that it was a comet impact and not the impact of an asteroid that caused the destruction in Siberia.

Recently, noctilucent clouds have been observed on the nights following launches of rockets that release large amounts of water vapor into the upper atmosphere.- Recently also noctilucent clouds have been observed, on the night following the rocket launch that release large amount of water vapor into the upper atmospher

This shows that it was a comet impact and not the impact of an asteroid that caused the destruction in Siberia.- Author concluded this cloud observed because of comet impact and not the asteroid impact because of which destruction in siberia happened

The argument depends on assuming which one of the following?- Question ask to find the assumption

clearly from the argument we can see that there is gap in the reasoning, we were only given the information about events but not how the noctilucent clouds form and just based on the observation, author concluded that it was comet effect. Think why did he concluded? what he assumed? there must be some connection between water vapor released and comet effect right? based on this thinking lets evaluate option choices
 
 (A) Comets but not asteroids release large amounts of water vapor into the upper atmosphere when they collide with Earth.- This directly bridges the gap, because the negated version will break the conclusion

(B) Noctilucent clouds are visible for many consecutive nights following the release of water vapor into the upper atmosphere.- this doesnot provide any information how the author arrived at conclusion

(C) Comets collide with Earth more frequently than asteroids do.- again irrelevant, how frequent they collide will not help

(D) Eyewitnesses have reported seeing noctilucent clouds after asteroids have collided with Earth.- if this is true then its a weakner

(E) The fact that noctilucent clouds are made of ice particles in the upper atmosphere was only recently discovered.- again irrelevant

hope this helps

guddo · Answer

On the nights immediately following the mysterious Tunguska event, which destroyed a tract of Siberian wilderness in 1908, eyewitnesses reported seeing noctilucent clouds—brilliant night-visible clouds made up of ice particles that form rarely and only at very high altitudes. Recently, noctilucent clouds have been observed on the nights following launches of rockets that release large amounts of water vapor into the upper atmosphere. This shows that it was a comet impact and not the impact of an asteroid that caused the destruction in Siberia.
 
 The argument depends on assuming which one of the following?

The argument says:
after the Tunguska event, people saw noctilucent clouds.
Recently, noctilucent clouds have also appeared after rockets released large amounts of water vapor high in the atmosphere.

So, the Tunguska event must also have released large amounts of water vapor, and therefore it must have been a comet, not an asteroid.

The key missing link  is that  a comet impact would release such water vapor, while an asteroid impact would not . Without that, the conclusion does not follow.

(A) Comets but not asteroids release large amounts of water vapor into the upper atmosphere when they collide with Earth.

This is correct. The argument needs exactly this assumption. Only then does the presence of noctilucent clouds support “comet rather than asteroid.”

(B) Noctilucent clouds are visible for many consecutive nights following the release of water vapor into the upper atmosphere.

This is not required. The argument only needs the clouds to appear after such a release, not for many nights.

(C) Comets collide with Earth more frequently than asteroids do.

This is irrelevant. Frequency of collision has nothing to do with the reasoning here.

(D) Eyewitnesses have reported seeing noctilucent clouds after asteroids have collided with Earth.

This would weaken the argument, not support it.

(E) The fact that noctilucent clouds are made of ice particles in the upper atmosphere was only recently discovered.

This is irrelevant. The timing of that discovery does not matter.

Answer: (A)

On the nights immediately following the mysterious Tunguska event, whi

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On the nights immediately following the mysterious Tunguska event, whi

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

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