Nebulas and Supernova

kaulnikhil wrote:Please put in your reasons for question no 25

Please put text here.

kaulnikhil wrote:Please put in your reasons for question no 25

21: D

22: B: Loss 1MO every 10000 years in 50000 years lost 5MO current mass less than 1.4MO so we can say it started with around 6-7MO.

23: A yes it reconcile contradictory facts.

24: B, yes B is an assumption as otherwise the data gathered is of no use, A is out as either of the CO or NH3 suffice so more molecules are combination of all molecules not needed. Other choices are vague.

25: protoplanetary nebulas are old giant stars whose dense cores have almost but not all rid themselves of fluffy envelopes.

C looks ok to me.

26: D looks to connect the statement about IR .

27: E, this option looks good as it covers several aspect of the three para,

So confirm the OA asap

21.D
22.B
23.A
24.B
25.A
26.D
27.E

kaulnikhil wrote:21.D
22.B
23.A
24.B
25.A
26.D
27.E

Wow great nearly all are correct, I was confused for 25 for option A, passage was good, but I didn't timed it, so not worth taking any pride in doing them correct, in case you have any question abt any of the options do let me know.

21. D

22. B
It has to be 7.0 or 6.0 or 5.0 and only 6.0 is metioned in the passage

23. D
There is a controversy on how the supernovas do not occur more often because more than 50% of all stars begin thier lives with mass greater than 1.4 M. This controversey is resolved by the view.

24. C
The author says that the rate loss can be used to calculate the age of the star(lines 28 - 34) and this rate loss is calculated by infrared observations of molecules in circumstellar cloud. Thus the author assumes that the age of a star is equal to its circumstellar cloud. Its bit of a stretch but I couldnt find any other convincing ansers.

25. E
Except E all the other options does not clearly state that the stars do not exhaust the fuel before the mass reduces below 1.4(which is one of the main points in the passage)

26. D
I am a bit shaky with this but evryhting else didnt seem right or didnt seem to be the logical extension of the passage

27. E

maihuna please provide your explanations for 23, 24 and 25.

ramesk_krish wrote:21. D


maihuna please provide your explanations for 23, 24 and 25.

I also got 25 wrong so I will only explain 23 24:

Ohh sorry I do not have the questions, let me download it again, this is the disadvantage of image texta..i will be back soon

ramesk_krish wrote:21. D


23. D
There is a controversy on how the supernovas do not occur more often because more than 50% of all stars begin thier lives with mass greater than 1.4 M. This controversey is resolved by the view.

24. C
The author says that the rate loss can be used to calculate the age of the star(lines 28 - 34) and this rate loss is calculated by infrared observations of molecules in circumstellar cloud. Thus the author assumes that the age of a star is equal to its circumstellar cloud. Its bit of a stretch but I couldnt find any other convincing ansers.

maihuna please provide your explanations for 23, 24 and 25.

See in 23 there is no controversy but discrepancy in expected an actual result. Expected is : Once the mass reaches the critical one i.e. 1.4 times Sun's, it should die prematurely because of the fact mentions, then the passage go on to mention with help of IR how these planets get rid of lot of mass and so survive rather then prematurely die. The line 18, first in second para refer to this example and so it helps to reconcile the conradictory facts. Hope I am clear.

In 24: Author assumption: In second para author goes on to mention how with help of wither CO or NH3 and the substance in surrounding cloud one may determine the age. Now if the surrounding cloud is not made of the substances from these IR + then one may not determine the same. So the negation of this fact makes the argument fall apart and so is a correct assumption.
No where it tries to assume that the age of star is equal to that of its circumstellar cloud, it talks about determining the age of IRC + whether it is equal to surrounding cloud is not doesn't affect the reasoning.