Heike Kamerlingh Onnes (18531926) a Dutch physicist discovered superc

Question

Heike Kamerlingh Onnes (1853–1926) a Dutch physicist discovered superconductivity in 1911. He used liquid helium as a coolant to study the electrical properties of metals at low temperatures. To everyone’s surprise, when mercury was cooled to about 4.2 kelvins, it suddenly lost all electrical resistance. This threshold is known as the critical temperature or  T_{c} . Other materials having ever higher critical temperatures were discovered slowly but surely during the first five decades of superconductivity research. All these superconductors were either pure metallic elements or intermetallic compounds (made of two or more metallic elements).

All this changed in 1986 with the discovery of high temperature superconductivity. During the first few years after this discovery,  T_{c}  values shot up, with mercury-barium-calcium-copper-oxide having a  T_{c}  of about 130K. This was a fantastically exciting time, but it soon became clear that the leading theory of how superconductivity arises does not explain the absence of resistance in these materials.

These compounds also pose a multitude of physical challenges. Initially, they were hard to make in either high-purity or single-crystal form, making the measurements of their fundamental properties difficult. In addition, the synthesis of wires is not easy: unlike the intermetallic superconductors, the individual grains that make up a piece of one of these oxides have to be aligned with respect to one another for the wire to have useful engineering properties. These problems left researchers and engineers wishing for a substance with the somewhat easier material properties of the intermetallic superconductors that also had a critical temperature significantly higher than 20K.    1 
 1. Which of the following is true about liquid helium?

A. It is the only substance used as a coolant
B. It can be used in low temperatures only.
C. It is used to lower the temperature of metals.
D. It is the best liquid used as a coolant.
E. It has a very low heat and thermal conductivity.

2 
 2. Which of the following can be inferred from the first paragraph

A. Superconductivity was first discovered long before the nineteenth century but surfaced in 1911.
B. A temperature under which a material acts as a superconductor is called critical temperature.
C. No substance at a temperature less than 4.2 kelvins act as a superconductor.
D. Substances with extremely high temperatures can be easily converted into superconductors
E. Intermetallic substances can be easily superconducted as compared to pure metallic substance

3 
 3. All of the following can be inferred from the passage EXCEPT

A. When compared to pure metallic substances, measuring the physical properties of an intermetallic substance is challenging.
B. Synthesizing of wires is one of the critical steps of Superconductivity.
C. Intermetallic superconductors can have a critical temperature higher than 20K.
D. Late in the nineteenth century superconductivity became more challenging.
E. Electrical properties of metals vary with temperature.

4 
 4. Which of the following is the most likely topic of the passage?

A. The work of Heike Kamerlingh for superconductivity
B. The role of critical temperatures in Superconductivity
C. Nineteenth century and Superconductivity
D. The History and Challenges of Superconductivity
E. Challenges of Superconductivity

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 Passage # 18  |  Date: 09 March 2023 
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Oppenheimer1945 · Answer

1. Which of the following is true about liquid helium?

A. It is the only substance used as a coolant ("only" is wrong)
B. It can be used in low temperatures only.(no mention)
 C. It is used to lower the temperature of metals. (True) 
D. It is the best liquid used as a coolant. ("best" is not mentioned anywhere)
E. It has a very low heat and thermal conductivity.(not mentioned)

He used liquid helium as a coolant to study the electrical properties of metals at low temperatures.

2. Which of the following can be inferred from the first paragraph

A. Superconductivity was first discovered long before the nineteenth century but surfaced in 1911.
 B. A temperature under which a material acts as a superconductor is called critical temperature. (True) 
C. No substance at a temperature less than 4.2 kelvins act as a superconductor.
D. Substances with extremely high temperatures can be easily converted into superconductors
E. Intermetallic substances can be easily superconducted as compared to pure metallic substance

everyone’s surprise, when mercury was cooled to about 4.2 kelvins, it suddenly lost all electrical resistance. This threshold is known as the critical temperature or Tc

3. All of the following can be inferred from the passage EXCEPT

A. When compared to pure metallic substances, measuring the physical properties of an intermetallic substance is challenging. (Not given) 
B. Synthesizing of wires is one of the critical steps of Superconductivity.
(the synthesis of wires is not easy: unlike the intermetallic superconductors)
C. Intermetallic superconductors can have a critical temperature higher than 20K.
(for a substance with the somewhat easier material properties of the intermetallic superconductors that also had a critical temperature significantly higher than 20K.)
D. Late in the nineteenth century superconductivity became more challenging.
(These compounds also pose a multitude of physical challenges.)
E. Electrical properties of metals vary with temperature.
(He used liquid helium as a coolant to study the electrical properties of metals at low temperatures. To everyone’s surprise, when mercury was cooled to about 4.2 kelvins, it suddenly lost all electrical resistance.)

4. Which of the following is the most likely topic of the passage?

A. The work of Heike Kamerlingh for superconductivity
B. The role of critical temperatures in Superconductivity
C. Nineteenth century and Superconductivity
 D. The History and Challenges of Superconductivity (whole passage talks about both histroty and challenges) - True 
E. Challenges of Superconductivity

Yanilcia · Answer

Hope you can see the word doc for my response for passage 2. march 9

Catman · Answer

1. Which of the following is true about liquid helium?

Refer to the line in the passage "He used liquid helium as a coolant to study the electrical properties of metals at low temperatures"
 
A. It is the only substance used as a coolant  ~ Incorrect, H.K.Onnes uses Helium as a coolant, but we cannot say that it was the only substance available to use as a coolant. May be other coolant were there, but they did not satisfy the research criterion of H.K.Onnes. They may be costly, less abundant, and due to other multiple reasons were not selected for the research.
 
B. It can be used in low temperatures only.  ~ Incorrect, in the above statement Helium is used as a coolant, we know that metals were raised to lower temperature for superconductivity, but from this we cannot conclude that Helium can be used in low temperatures only. Also, coolant is one of the use of the Helium, may be other uses of Helium require it to be at higher temperature or room(natural) temperature greater than low temperature.
 
C. It is used to lower the temperature of metals.  ~ Correct, this is the exactly mentioned in the above line that Helium is used to lower the temperature of metals to study their electrical properties. This is also confirmed by the line "To everyone’s surprise, when mercury was cooled to about 4.2 kelvins, it suddenly lost all electrical resistance." Here Helium as a coolant able to achieve the task of reducing the Mercury temperature to about 4.2 Kelvins.
 
D. It is the best liquid used as a coolant.  ~ Incorrect, the use of adjective best is not used to describe Helium as a coolant. We don't know why H.K.Onnes uses Helium as a coolant may be it was easily available, less costly than other. There are multiple reasons why He chooses Helium as a coolant, we cannot certainly say that he chooses Helium because it is the best liquid.
 
E. It has a very low heat and thermal conductivity.  ~ Incorrect, we don't know about the heat and thermal conductivity of the helium, it's use only as a coolant is discussed.

2. Which of the following can be inferred from the first paragraph

A. Superconductivity was first discovered long before the nineteenth century but surfaced in 1911.  ~ Incorrect, it is mentioned in the first paragraph that H. K. Onnes discovered superconductivity in 1911. There is no mention that it was discovered earlier, but surfaced by H. K. Onnes .
 
B. A temperature under which a material acts as a superconductor is called critical temperature.  ~ Correct, refer to the line "To everyone’s surprise, when mercury was cooled to about 4.2 kelvins, it suddenly lost all electrical resistance. This threshold is known as the critical temperature or Tc".

C. No substance at a temperature less than 4.2 kelvins act as a superconductor.  ~ Incorrect, Mercury when cooled to about 4.2K lost all electrical resistance and act as a superconductor. So temperature of 4.2 Kelvins is the threshold for mercury as a metal. We don't know what are the threshold temperature for other metals.

D. Substances with extremely high temperatures can be easily converted into superconductors   ~ Incorrect, as per the passage after the discovery of superconductivity by H .K. Onnes, other materials were discovered which has higher temperature than the threshold temperature of 4.2k . But, we cannot confirm that conversion of these materials into semiconductor became easier or not.

E. Intermetallic substances can be easily superconducted as compared to pure metallic substance  ~ Incorrect, new superconductors which were discovered after mercury does have higher critical temperature. But we don't know between these newer superconductors intermetallic substance or metallic substance which can be easily superconducted.

3. All of the following can be inferred from the passage EXCEPT

A. When compared to pure metallic substances, measuring the physical properties of an intermetallic substance is challenging.  ~ Correct, refer to the line "These compounds also pose a multitude of physical challenges. Initially, they were hard to make in either high-purity or single-crystal form, making the measurements of their fundamental properties difficult" . In this fundamental properties of intermetallic substance are mentioned, the fundamental properties is not equivalent to the physical properties. Also in the last line of the passage "These problems left researchers and engineers wishing for a substance with the somewhat easier material properties of the intermetallic superconductors that also had a critical temperature significantly higher than 20K." Material properties is mentioned which is equal to the chemical compostion and not the physical property of the intermetallic substance.

B. Synthesizing of wires is one of the critical steps of Superconductivity.  ~ Incorrect, mentioned in the passage refer to the line "In addition, the synthesis of wires is not easy: unlike the intermetallic superconductors, the individual grains that make up a piece of one of these oxides have to be aligned with respect to one another for the wire to have useful engineering properties."

C. Intermetallic superconductors can have a critical temperature higher than 20K.   ~Incorrect, mentioned in the passage refer to the line " During the first few years after this discovery, Tc values shot up, with mercury-barium-calcium-copper-oxide having a Tc of about 130K". So clearly intermetallic superconductors can have a Tc higher than 20k.
 
D. Late in the nineteenth century superconductivity became more challenging.  ~ Incorrect, passage mentions that in 1986, with use of intermetallic compounds the threshold temperature value shot up, but these intermetallic compounds poses multitude of physical challenges. This is further confirm by last line "These problems left researchers and engineers wishing for a substance with the somewhat easier material properties of the intermetallic superconductors that also had a critical temperature significantly higher than 20K." So superconductivity has became more challenging in the late 19th century.

E. Electrical properties of metals vary with temperature.  ~ Incorrect, as per the passage beyond a threshold temperature, metals lost all electrical resistance and became superconductor. Refer to the line "To everyone’s surprise, when mercury was cooled to about 4.2 kelvins, it suddenly lost all electrical resistance."
 
 4. Which of the following is the most likely topic of the passage? 
 
A. The work of Heike Kamerlingh for superconductivity  ~ Incorrect, the work of H.K.Onnes is described to show how the discovery of Superconductivity is made by him. Later the passage transition to increasing the threshold temperature of intermetallic compounds and what are the challenges associated with these intermetallic compounds to be used as a semiconductor.

B. The role of critical temperatures in Superconductivity  ~ Incorrect, author initially mentions that critical temperature is the threshold temperature for superconductivity. But by increasing the temperature in the intermetallic compounds, new problems related to material properties have arise.So, increasing the critical temperature is not the only criterion for supercondutivity.

C. Nineteenth century and Superconductivity  ~ Incorrect, Passage mentions that the discovery of superconductivity was made in the 1911, but in later years it was discovered that the initial theory "how superconductivity arises" did not explain the physical challenges associated with the intermetallic compounds. Although passage mentions the Superconductivity during the timeline of 19th century, but it is not focussed on the timeline of the 19th century. It is more focussed on the challenges and the history of the Superconductivity.

D. The History and Challenges of Superconductivity  ~ Correct, this statement completely describes the passage. Passage begins with a brief history of superconductivity, how it is discovered by H.K.Onnes by use of metal mercury and later during the 19th century other metallic and intermetallic compounds were discovered. After that physical challenges associated with usage of intermetallic compounds as semiconductors were mentioned.

E. Challenges of Superconductivity  ~ Incorrect, between option D and E, D will be a more apt choice as passage begins with a brief history of superconductivity, how it is discovered by H.K.Onnes by use of metal mercury and later during the 19th century other metallic and intermetallic compounds were discovered. Although E covers the challenges of superconductivity mentioned in later parts of the passage, it fails to capture the history in the first paragraph.

pintukr · Answer

1. Which of the following is true about liquid helium?

A. It is the only substance used as a coolant
 no specific conclusions can be drawn regarding the liquid helium being the 'only' substance used as a coolant

B. It can be used in low temperatures only.
 temperature specifications for use of liquid helium not highlighted in the passage

C. It is used to lower the temperature of metals.
  use of liquid helium to get to the 'critical temperature' below which the element ...alludes to this fact..CORRECT answer

D. It is the best liquid used as a coolant.
 'best' specification for liquid helium..can't be drawn using the facts presented in the passage

E. It has a very low heat and thermal conductivity.
 conductivity aspects of liquid helium not discussed in the passage

2. Which of the following can be inferred from the first paragraph

A. Superconductivity was first discovered long before the nineteenth century but surfaced in 1911.
 incorrect, since it has been stated that superconductivity was discovered in 1911

B. A temperature under which a material acts as a superconductor is called critical temperature.
  clearly highlighted vide lines 5-6 of paragraph 1..CORRECT answer

C. No substance at a temperature less than 4.2 kelvins act as a superconductor.
 can't be ascertained using the facts in the passage

D. Substances with extremely high temperatures can be easily converted into superconductors
 no such conclusions can be drawn that substances with extremely high temperatures can be easily converted into superconductors

E. Intermetallic substances can be easily superconducted as compared to pure metallic substance
 comparative superconductivity potential not deliberated upon

3. All of the following can be inferred from the passage EXCEPT

A. When compared to pure metallic substances, measuring the physical properties of an inter-metallic substance is challenging.
 no inferences can be drawn with respective to comparative potential of the measurement of physical properties of pure metallic and inter-metallic substances..CORRECT answer

B. Synthesizing of wires is one of the critical steps of Superconductivity.
 highighted in paragraph 3

C. Intermetallic superconductors can have a critical temperature higher than 20K.
 It can be inferred using the last two lines of paragraph 3

D. Late in the nineteenth century superconductivity became more challenging.
 superconductivity in compounds (discovered in late 19th century) posed challenges, particularly relating to the synthesis of wires..can be inferred

E. Electrical properties of metals vary with temperature
 can be inferred, as Critical Temperature clearly alludes to this aspect

4. Which of the following is the most likely topic of the passage?

A. The work of Heike Kamerlingh for superconductivity
 work of Heike Kamerlingh..only covered in paragraph 1

B. The role of critical temperatures in Superconductivity
 too limited in scope; the passage highlights the challenges of Superconductivity as well

C. Nineteenth century and Superconductivity
 only 1911 and 1986 related developments pertaining to Superconductivity have been covered in the passage

D. The History and Challenges of Superconductivity
  The History (covered in paragraph 1), while the Challenges of Superconductivity (covered in paragraphs 2 and 3)..CORRECT answer

E. Challenges of Superconductivity
limited in scope vis -a-vis prompt (D)

IMO, the sequence of correct answers should be CBAD

Elite097 · Answer

1. Which of the following is true about liquid helium?

A. It is the only substance used as a coolant
Helium was used as a coolant is not same as helium being the 'only' coolant

B. It can be used in low temperatures only.
It was used at low temp but it does not mean it can only be used at low temp

C. It is used to lower the temperature of metals.
Since it is a coolant thus we can infer this

D. It is the best liquid used as a coolant.
We cannot say it is the 'best' definitively from the info given

E. It has a very low heat and thermal conductivity.
We cannot conclude this

Ans C

2. Which of the following can be inferred from the first paragraph

A. Superconductivity was first discovered long before the nineteenth century but surfaced in 1911.
"a Dutch physicist discovered superconductivity in 1911" gives us no idea of discovery pre 1911

B. A temperature under which a material acts as a superconductor is called critical temperature.
" when mercury was cooled to about 4.2 kelvins, it suddenly lost all electrical resistance. This threshold is known as the critical temperature or Tc" indicates this

C. No substance at a temperature less than 4.2 kelvins act as a superconductor.
This is too extreme. We cannot infer this

D. Substances with extremely high temperatures can be easily converted into superconductors
We don't know if these substances can be easily converted into superconductors.

E. Intermetallic substances can be easily superconducted as compared to pure metallic substance
No such comparison can be drawn

Ans B

3. All of the following can be inferred from the passage EXCEPT

A. When compared to pure metallic substances, measuring the physical properties of an intermetallic substance is challenging.
This cannot be inferred as " they were hard to make in either high-purity or single-crystal form, making the measurements of their fundamental properties difficult" is in context of oxides not intermetallic compounds

B. Synthesizing of wires is one of the critical steps of Superconductivity.
"In addition, the synthesis of wires is not easy: unlike the intermetallic superconductors, the individual grains that make up a piece of one of these oxides have to be aligned with respect to one another for the wire to have  useful engineering properties " indicates this

C. Intermetallic superconductors can have a critical temperature higher than 20K.
"engineers wishing for a substance with the somewhat easier material properties of the intermetallic superconductors that also had a critical temperature significantly higher than 20K" indicates this

D. Late in the nineteenth century superconductivity became more challenging.
"This was a fantastically exciting time, but it soon became clear that the leading theory of how superconductivity arises does not explain the absence of resistance in these materials" indicates this

E. Electrical properties of metals vary with temperature.
"mercury was cooled to about 4.2 kelvins, it suddenly lost all electrical resistance" indicates this

Ans D

4. Which of the following is the most likely topic of the passage?

A. The work of Heike Kamerlingh for superconductivity
There is barely anything discussed about his work

B. The role of critical temperatures in Superconductivity
This is only a small part of the passage

C. Nineteenth century and Superconductivity
Nothing is discussed about nineteenth century

D. The History and Challenges of Superconductivity
First para is about history of super conductivity and the rest two are about challenges as indicated by "but it soon became clear that the leading theory of how superconductivity arises does not explain the absence of resistance in these materials."

E. Challenges of Superconductivity
This is one aspect of the passage

Ans D

$!vakumar.m · Answer

1. Which of the following is true about liquid helium?

A. It is the only substance used as a coolant  
Option A is incorrect because the author doesn’t mention that helium is the only substance that can be used as a coolant.

B. It can be used in low temperatures only.  
Option B is incorrect because the author mentions that helium is used to lower temperatures of other metals and not that helium can be used in low temperatures only.

C. It is used to lower the temperature of metals.  
Option C is correct because the author mentions that HKO used liquid helium as a coolant to study the electrical properties of metals at low temperatures.

D. It is the best liquid used as a coolant.  
Option D is incorrect because the author doesn’t mention that helium is the best liquid used as a coolant.

E. It has a very low heat and thermal conductivity.  
Option E is incorrect because the author doesn’t mention that helium has a very low heat and thermal conductivity.

2. Which of the following can be inferred from the first paragraph 
From the sentences in first paragraph - " To everyone’s surprise, when mercury was cooled to about 4.2 kelvins, it suddenly lost all electrical resistance. This threshold is known as the critical temperature or Tc." - we can infer that   option B   “A temperature under which a material acts as a superconductor is called critical temperature”  is correct.

4. Which of the following is the most likely topic of the passage? 
The most suitable topic of the passage is   option D   – “The History and Challenges of Superconductivity” as the author presents discusses a historical overview of the discovery of superconductivity and how it evolved over time, as well as the challenges faced by researchers in understanding and developing high temperature superconductors.

A. The work of Heike Kamerlingh for superconductivity  
Incorrect. Though the author begins with the work of HK, however, this is not the focus of the passage.

B. The role of critical temperatures in Superconductivity  
Incorrect. The role of Tc is not the focus of the passage.

C. Nineteenth century and Superconductivity  
Incorrect. The author traces the research involved in the field of superconductivity and goes on to explain the current issues and challenges faced by researchers and scientists. However, the work done in Nineteenth century is not the focus of the passage.

E. Challenges of Superconductivity  
Incorrect. Again, this is not the focus of the passage.

Sajjad1994 · Answer

Explanation

1. Which of the following is true about liquid helium?

Explanation

The correct answer is  C.  Liquid helium is used as a coolant to lower the temperature of metals, as mentioned in the passage: "He used liquid helium as a coolant to study the electrical properties of metals at low temperatures."

A  is incorrect because the passage doesn't say that liquid helium is the only substance used as a coolant.

B  is incorrect because while liquid helium is used at low temperatures, it can also be used at higher temperatures.

D  is incorrect because the passage doesn't make any comparison between liquid helium and other coolants to determine which is the best.

E  is incorrect because the passage doesn't provide any information on the heat and thermal conductivity of liquid helium.

Answer: C

Sajjad1994 · Answer

Explanation

2. Which of the following can be inferred from the first paragraph

Explanation

The first paragraph discusses the discovery of superconductivity by Heike Kamerlingh Onnes and the critical temperature (Tc) at which a material acts as a superconductor. The paragraph clearly states, "This threshold is known as the critical temperature or Tc." Therefore,  option B  is the correct answer.

Option A  is incorrect as the paragraph does not discuss any previous discoveries of superconductivity before 1911.

Option C  is incorrect as the paragraph only mentions that mercury loses all electrical resistance when cooled to about 4.2 kelvins, not that no substance can act as a superconductor at a temperature less than 4.2 kelvins.

Option D  is incorrect as the paragraph does not state that substances with extremely high temperatures can be easily converted into superconductors.

Option E  is incorrect as the paragraph does not provide any comparison between the ease of superconducting intermetallic substances and pure metallic substances.

Answer: B

Sajjad1994 · Answer

Explanation

3. All of the following can be inferred from the passage EXCEPT

Explanation

The passage states that  "Other materials having ever higher critical temperatures were discovered slowly but surely during the first five decades of superconductivity research. All these superconductors were either pure metallic elements or intermetallic compounds (made of two or more metallic elements)."  Therefore, option D cannot be inferred from the passage as it suggests the opposite. The passage talks about the discovery of superconductivity in 1911 and the subsequent discovery of superconductors with higher critical temperatures, including high-temperature superconductivity in 1986. It also discusses the challenges of measuring the physical properties of high-temperature intermetallic superconductors and synthesizing wires from them. The passage also explains that the critical temperature of some intermetallic superconductors can be higher than 20K. The passage also mentions that when metals are cooled to low temperatures, they may lose all electrical resistance, which indicates that the electrical properties of metals vary with temperature. Therefore, options A, B, C, and E can all be inferred from the passage.

Answer: D

Sajjad1994 · Answer

Explanation

4. Which of the following is the most likely topic of the passage?

Explanation

The most likely topic of the passage is D. The History and Challenges of Superconductivity. The passage discusses the discovery of superconductivity by Heike Kamerlingh Onnes in 1911, the subsequent discovery of high temperature superconductivity in 1986, and the challenges associated with synthesizing and measuring the physical properties of superconductors.

Answer: D

Sajjad1994 · Answer

Hello Everyone!

OAs are revealed, OE is posted, and the competition mode is off now.

Here is the result on this one.

Elite097: 80
Catman: 75
pintukr: 70
sivakumarm786: 60

Last day passages are posted, put in your full efforts and then we will announce the result and conclude this quiz.

Good luck!

Sajjad1994 · Answer

No! I cannot see any response posted by you. Let me know if I can help you.

Catman · Answer

Sajjad1994 , I am awaiting my result on this one? Please rate my explanations.Thank you.

Posted from my mobile device

Elite097 · Answer

Sajjad1994 . I by mistake wwrote A as an ans to A but my explanation clearly justifies D. Could you please share the revised scoring and edit that response? Sorry for the same

Sajjad1994 · Answer

Wow! In my backend record (I save in my computer) I recorded your score 16/20. but here mentioned wrongly.

Updated Now!

Its_me_aka_ak · Answer

Sajjad1994 
why is A wrong in Q3 when the passage suggest the opposite of what the options says "the synthesis of wires is not easy: unlike the intermetallic superconductors, the individual grains that make up a piece of one of these oxides have to be aligned with respect to one another for the wire to have useful engineering properties"

Sajjad1994 · Answer

This is a type of  half right   half wrong  answer choice. The start of the question can be inferred correctly from the passage but the later part contradicts on the other hand answer  option (D)  altogether wrong and cannot be inferred. Hence  (D)  has slightly edge over  (A).

PS: I accept the answer to this question stands controversial and answer option A and D both can be defended with different reasoning. According to the passage measuring the physical properties of both the intermetallic substances and the pure metallic substances both are challenging.

Its_me_aka_ak · Answer

I agree. A and D both seemed to be not directly inferred out the passage. i just thought that D is comparatively more inferable. Thanks for the revert

Heike Kamerlingh Onnes (18531926) a Dutch physicist discovered superc

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Heike Kamerlingh Onnes (18531926) a Dutch physicist discovered superc

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

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