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Directions: Read the passages and choose the best answer to each question.
Passage
The Earth’s magnetic field is one of its most significant natural phenomena. For centuries, the field has been used to aid navigation and exploration, and has been vital to many major discoveries. The magnetic field of the Earth extends several thousands of miles into space. It has the effect of shielding the Earth from solar wind, protecting the planet from dangerous high-energy particles and radiation. The exact source of the Earth’s magnetic field is not certain. The following two Scientists attempt to explain the phenomenon.
Scientist 1
The Earth’s magnetic field is similar to that of a bar magnet tilted 11 degrees from the spin axis of the Earth.
The magnetic field of a bar magnet, or any other type of permanent magnet, is created by the coordinated motions of electrons within iron atoms. It is widely accepted that the Earth’s core consists of metals. The inner core is 70% as wide as the moon and consists of a solid iron ball, which would exhibit properties of ferromagnetism (the natural magnetic tendency of iron). The core has its own rotation and is surrounded by a “sea” of molten rock. The magnetic field grows and wanes, and the Earth’s poles drift and occasionally flip as the rotation of the core changes. The poles of the magnetic field have “flipped” many times due to the fluctuations in the rotation of the solid inner core. Other fluctuations in the magnetic field that can occur on a daily basis are largely the result of interference by solar wind.
Scientist 2
The Earth’s magnetic field is attributed to a dynamo effect of circulating electric current in the molten outer core. Electric currents cause magnetic fields; therefore, the circulating electric currents in the Earth’s molten metallic core are the origin of the magnetic field. When conducting fluid flows across an existing magnetic field, electric currents are induced, creating another magnetic field. When this magnetic field reinforces the original magnetic field, a dynamo is created which sustains itself.
Sitting atop the hot, iron inner core, the Earth’s molten outer core churns and moves. The outer core also has cyclones or whirlpools powered by the Coriolis effects of Earth’s rotation. These complex and unpredictable motions generate the fluctuating magnetic field. The outer core is seething, swirling, and turbulent, which has been detected by the constant changes and reversals in polarity throughout the planet’s history. Further, iron has a special characteristic.
When it is hotter than 1043 K, its Curie temperature, iron loses its magnetic properties. Therefore the Earth’s magnetic field is caused not by magnetised iron deposits, but mostly by electric currents in the liquid outer core.
Q. Which of the following statements about the Earth’s core was implied by Scientist 2?
  • a)
    The Earth’s inner core is a rotating mass of iron.
  • b)
    The Earth’s inner core is solely responsible for the magnetic field.
  • c)
    The Earth’s core is iron and possesses properties similar to a bar magnet.
  • d)
    The Earth’s core has a temperature above 1043 K.
Correct answer is option 'D'. Can you explain this answer?
Most Upvoted Answer
Directions:Read the passages and choose the best answer to each questi...
Scientist 2 states that when iron is “hotter than 1043K, its Curie temperature, iron loses its magnetic properties.” The scientist is
implying that the Earth’s core has a temperature above 1043K; therefore, it has lost its magnetic properties and cannot cause the Earth’s magnetic fields. Answer choice B can be eliminated because this is the viewpoint of Scientist 1 only.
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Directions:Read the passages and choose the best answer to each question.PassageThe Earth’s magnetic field is one of its most significant natural phenomena. For centuries, the field has been used to aid navigation and exploration, and has been vital to many major discoveries. The magnetic field of the Earth extends several thousands of miles into space. It has the effect of shielding the Earth from solar wind, protecting the planet from dangerous high-energy particles and radiation. The exact source of the Earth’s magnetic field is not certain. The following two Scientists attempt to explain the phenomenon.Scientist 1The Earth’s magnetic field is similar to that of a bar magnet tilted 11 degrees from the spin axis of the Earth.The magnetic field of a bar magnet, or any other type of permanent magnet, is created by the coordinated motions of electrons within iron atoms. It is widely accepted that the Earth’s core consists of metals. The inner core is 70% as wide as the moon and consists of a solid iron ball, which would exhibit properties of ferromagnetism (the natural magnetic tendency of iron). The core has its own rotation and is surrounded by a “sea” of molten rock. The magnetic field grows and wanes, and the Earth’s poles drift and occasionally flip as the rotation of the core changes. The poles of the magnetic field have “flipped” many times due to the fluctuations in the rotation of the solid inner core. Other fluctuations in the magnetic field that can occur on a daily basis are largely the result of interference by solar wind.Scientist 2The Earth’s magnetic field is attributed to a dynamo effect of circulating electric current in the molten outer core. Electric currents cause magnetic fields; therefore, the circulating electric currents in the Earth’s molten metallic core are the origin of the magnetic field. When conducting fluid flows across an existing magnetic field, electric currents are induced, creating another magnetic field. When this magnetic field reinforces the original magnetic field, a dynamo is created which sustains itself.Sitting atop the hot, iron inner core, the Earth’s molten outer core churns and moves. The outer core also has cyclones or whirlpools powered by the Coriolis effects of Earth’s rotation. These complex and unpredictable motions generate the fluctuating magnetic field. The outer core is seething, swirling, and turbulent, which has been detected by the constant changes and reversals in polarity throughout the planet’s history. Further, iron has a special characteristic.When it is hotter than 1043 K, its Curie temperature, iron loses its magnetic properties. Therefore the Earth’s magnetic field is caused not by magnetised iron deposits, but mostly by electric currents in the liquid outer core.Q.Which of the following statements about the Earth’s core was implied by Scientist 2?a)The Earth’s inner core is a rotating mass of iron.b)The Earth’s inner core is solely responsible for the magnetic field.c)The Earth’s core is iron and possesses properties similar to a bar magnet.d)The Earth’s core has a temperature above 1043 K.Correct answer is option 'D'. Can you explain this answer?
Question Description
Directions:Read the passages and choose the best answer to each question.PassageThe Earth’s magnetic field is one of its most significant natural phenomena. For centuries, the field has been used to aid navigation and exploration, and has been vital to many major discoveries. The magnetic field of the Earth extends several thousands of miles into space. It has the effect of shielding the Earth from solar wind, protecting the planet from dangerous high-energy particles and radiation. The exact source of the Earth’s magnetic field is not certain. The following two Scientists attempt to explain the phenomenon.Scientist 1The Earth’s magnetic field is similar to that of a bar magnet tilted 11 degrees from the spin axis of the Earth.The magnetic field of a bar magnet, or any other type of permanent magnet, is created by the coordinated motions of electrons within iron atoms. It is widely accepted that the Earth’s core consists of metals. The inner core is 70% as wide as the moon and consists of a solid iron ball, which would exhibit properties of ferromagnetism (the natural magnetic tendency of iron). The core has its own rotation and is surrounded by a “sea” of molten rock. The magnetic field grows and wanes, and the Earth’s poles drift and occasionally flip as the rotation of the core changes. The poles of the magnetic field have “flipped” many times due to the fluctuations in the rotation of the solid inner core. Other fluctuations in the magnetic field that can occur on a daily basis are largely the result of interference by solar wind.Scientist 2The Earth’s magnetic field is attributed to a dynamo effect of circulating electric current in the molten outer core. Electric currents cause magnetic fields; therefore, the circulating electric currents in the Earth’s molten metallic core are the origin of the magnetic field. When conducting fluid flows across an existing magnetic field, electric currents are induced, creating another magnetic field. When this magnetic field reinforces the original magnetic field, a dynamo is created which sustains itself.Sitting atop the hot, iron inner core, the Earth’s molten outer core churns and moves. The outer core also has cyclones or whirlpools powered by the Coriolis effects of Earth’s rotation. These complex and unpredictable motions generate the fluctuating magnetic field. The outer core is seething, swirling, and turbulent, which has been detected by the constant changes and reversals in polarity throughout the planet’s history. Further, iron has a special characteristic.When it is hotter than 1043 K, its Curie temperature, iron loses its magnetic properties. Therefore the Earth’s magnetic field is caused not by magnetised iron deposits, but mostly by electric currents in the liquid outer core.Q.Which of the following statements about the Earth’s core was implied by Scientist 2?a)The Earth’s inner core is a rotating mass of iron.b)The Earth’s inner core is solely responsible for the magnetic field.c)The Earth’s core is iron and possesses properties similar to a bar magnet.d)The Earth’s core has a temperature above 1043 K.Correct answer is option 'D'. Can you explain this answer? for ACT 2025 is part of ACT preparation. The Question and answers have been prepared according to the ACT exam syllabus. Information about Directions:Read the passages and choose the best answer to each question.PassageThe Earth’s magnetic field is one of its most significant natural phenomena. For centuries, the field has been used to aid navigation and exploration, and has been vital to many major discoveries. The magnetic field of the Earth extends several thousands of miles into space. It has the effect of shielding the Earth from solar wind, protecting the planet from dangerous high-energy particles and radiation. The exact source of the Earth’s magnetic field is not certain. The following two Scientists attempt to explain the phenomenon.Scientist 1The Earth’s magnetic field is similar to that of a bar magnet tilted 11 degrees from the spin axis of the Earth.The magnetic field of a bar magnet, or any other type of permanent magnet, is created by the coordinated motions of electrons within iron atoms. It is widely accepted that the Earth’s core consists of metals. The inner core is 70% as wide as the moon and consists of a solid iron ball, which would exhibit properties of ferromagnetism (the natural magnetic tendency of iron). The core has its own rotation and is surrounded by a “sea” of molten rock. The magnetic field grows and wanes, and the Earth’s poles drift and occasionally flip as the rotation of the core changes. The poles of the magnetic field have “flipped” many times due to the fluctuations in the rotation of the solid inner core. Other fluctuations in the magnetic field that can occur on a daily basis are largely the result of interference by solar wind.Scientist 2The Earth’s magnetic field is attributed to a dynamo effect of circulating electric current in the molten outer core. Electric currents cause magnetic fields; therefore, the circulating electric currents in the Earth’s molten metallic core are the origin of the magnetic field. When conducting fluid flows across an existing magnetic field, electric currents are induced, creating another magnetic field. When this magnetic field reinforces the original magnetic field, a dynamo is created which sustains itself.Sitting atop the hot, iron inner core, the Earth’s molten outer core churns and moves. The outer core also has cyclones or whirlpools powered by the Coriolis effects of Earth’s rotation. These complex and unpredictable motions generate the fluctuating magnetic field. The outer core is seething, swirling, and turbulent, which has been detected by the constant changes and reversals in polarity throughout the planet’s history. Further, iron has a special characteristic.When it is hotter than 1043 K, its Curie temperature, iron loses its magnetic properties. Therefore the Earth’s magnetic field is caused not by magnetised iron deposits, but mostly by electric currents in the liquid outer core.Q.Which of the following statements about the Earth’s core was implied by Scientist 2?a)The Earth’s inner core is a rotating mass of iron.b)The Earth’s inner core is solely responsible for the magnetic field.c)The Earth’s core is iron and possesses properties similar to a bar magnet.d)The Earth’s core has a temperature above 1043 K.Correct answer is option 'D'. Can you explain this answer? covers all topics & solutions for ACT 2025 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Directions:Read the passages and choose the best answer to each question.PassageThe Earth’s magnetic field is one of its most significant natural phenomena. For centuries, the field has been used to aid navigation and exploration, and has been vital to many major discoveries. The magnetic field of the Earth extends several thousands of miles into space. It has the effect of shielding the Earth from solar wind, protecting the planet from dangerous high-energy particles and radiation. The exact source of the Earth’s magnetic field is not certain. The following two Scientists attempt to explain the phenomenon.Scientist 1The Earth’s magnetic field is similar to that of a bar magnet tilted 11 degrees from the spin axis of the Earth.The magnetic field of a bar magnet, or any other type of permanent magnet, is created by the coordinated motions of electrons within iron atoms. It is widely accepted that the Earth’s core consists of metals. The inner core is 70% as wide as the moon and consists of a solid iron ball, which would exhibit properties of ferromagnetism (the natural magnetic tendency of iron). The core has its own rotation and is surrounded by a “sea” of molten rock. The magnetic field grows and wanes, and the Earth’s poles drift and occasionally flip as the rotation of the core changes. The poles of the magnetic field have “flipped” many times due to the fluctuations in the rotation of the solid inner core. Other fluctuations in the magnetic field that can occur on a daily basis are largely the result of interference by solar wind.Scientist 2The Earth’s magnetic field is attributed to a dynamo effect of circulating electric current in the molten outer core. Electric currents cause magnetic fields; therefore, the circulating electric currents in the Earth’s molten metallic core are the origin of the magnetic field. When conducting fluid flows across an existing magnetic field, electric currents are induced, creating another magnetic field. When this magnetic field reinforces the original magnetic field, a dynamo is created which sustains itself.Sitting atop the hot, iron inner core, the Earth’s molten outer core churns and moves. The outer core also has cyclones or whirlpools powered by the Coriolis effects of Earth’s rotation. These complex and unpredictable motions generate the fluctuating magnetic field. The outer core is seething, swirling, and turbulent, which has been detected by the constant changes and reversals in polarity throughout the planet’s history. Further, iron has a special characteristic.When it is hotter than 1043 K, its Curie temperature, iron loses its magnetic properties. Therefore the Earth’s magnetic field is caused not by magnetised iron deposits, but mostly by electric currents in the liquid outer core.Q.Which of the following statements about the Earth’s core was implied by Scientist 2?a)The Earth’s inner core is a rotating mass of iron.b)The Earth’s inner core is solely responsible for the magnetic field.c)The Earth’s core is iron and possesses properties similar to a bar magnet.d)The Earth’s core has a temperature above 1043 K.Correct answer is option 'D'. Can you explain this answer?.
Solutions for Directions:Read the passages and choose the best answer to each question.PassageThe Earth’s magnetic field is one of its most significant natural phenomena. For centuries, the field has been used to aid navigation and exploration, and has been vital to many major discoveries. The magnetic field of the Earth extends several thousands of miles into space. It has the effect of shielding the Earth from solar wind, protecting the planet from dangerous high-energy particles and radiation. The exact source of the Earth’s magnetic field is not certain. The following two Scientists attempt to explain the phenomenon.Scientist 1The Earth’s magnetic field is similar to that of a bar magnet tilted 11 degrees from the spin axis of the Earth.The magnetic field of a bar magnet, or any other type of permanent magnet, is created by the coordinated motions of electrons within iron atoms. It is widely accepted that the Earth’s core consists of metals. The inner core is 70% as wide as the moon and consists of a solid iron ball, which would exhibit properties of ferromagnetism (the natural magnetic tendency of iron). The core has its own rotation and is surrounded by a “sea” of molten rock. The magnetic field grows and wanes, and the Earth’s poles drift and occasionally flip as the rotation of the core changes. The poles of the magnetic field have “flipped” many times due to the fluctuations in the rotation of the solid inner core. Other fluctuations in the magnetic field that can occur on a daily basis are largely the result of interference by solar wind.Scientist 2The Earth’s magnetic field is attributed to a dynamo effect of circulating electric current in the molten outer core. Electric currents cause magnetic fields; therefore, the circulating electric currents in the Earth’s molten metallic core are the origin of the magnetic field. When conducting fluid flows across an existing magnetic field, electric currents are induced, creating another magnetic field. When this magnetic field reinforces the original magnetic field, a dynamo is created which sustains itself.Sitting atop the hot, iron inner core, the Earth’s molten outer core churns and moves. The outer core also has cyclones or whirlpools powered by the Coriolis effects of Earth’s rotation. These complex and unpredictable motions generate the fluctuating magnetic field. The outer core is seething, swirling, and turbulent, which has been detected by the constant changes and reversals in polarity throughout the planet’s history. Further, iron has a special characteristic.When it is hotter than 1043 K, its Curie temperature, iron loses its magnetic properties. Therefore the Earth’s magnetic field is caused not by magnetised iron deposits, but mostly by electric currents in the liquid outer core.Q.Which of the following statements about the Earth’s core was implied by Scientist 2?a)The Earth’s inner core is a rotating mass of iron.b)The Earth’s inner core is solely responsible for the magnetic field.c)The Earth’s core is iron and possesses properties similar to a bar magnet.d)The Earth’s core has a temperature above 1043 K.Correct answer is option 'D'. Can you explain this answer? in English & in Hindi are available as part of our courses for ACT. Download more important topics, notes, lectures and mock test series for ACT Exam by signing up for free.
Here you can find the meaning of Directions:Read the passages and choose the best answer to each question.PassageThe Earth’s magnetic field is one of its most significant natural phenomena. For centuries, the field has been used to aid navigation and exploration, and has been vital to many major discoveries. The magnetic field of the Earth extends several thousands of miles into space. It has the effect of shielding the Earth from solar wind, protecting the planet from dangerous high-energy particles and radiation. The exact source of the Earth’s magnetic field is not certain. The following two Scientists attempt to explain the phenomenon.Scientist 1The Earth’s magnetic field is similar to that of a bar magnet tilted 11 degrees from the spin axis of the Earth.The magnetic field of a bar magnet, or any other type of permanent magnet, is created by the coordinated motions of electrons within iron atoms. It is widely accepted that the Earth’s core consists of metals. The inner core is 70% as wide as the moon and consists of a solid iron ball, which would exhibit properties of ferromagnetism (the natural magnetic tendency of iron). The core has its own rotation and is surrounded by a “sea” of molten rock. The magnetic field grows and wanes, and the Earth’s poles drift and occasionally flip as the rotation of the core changes. The poles of the magnetic field have “flipped” many times due to the fluctuations in the rotation of the solid inner core. Other fluctuations in the magnetic field that can occur on a daily basis are largely the result of interference by solar wind.Scientist 2The Earth’s magnetic field is attributed to a dynamo effect of circulating electric current in the molten outer core. Electric currents cause magnetic fields; therefore, the circulating electric currents in the Earth’s molten metallic core are the origin of the magnetic field. When conducting fluid flows across an existing magnetic field, electric currents are induced, creating another magnetic field. When this magnetic field reinforces the original magnetic field, a dynamo is created which sustains itself.Sitting atop the hot, iron inner core, the Earth’s molten outer core churns and moves. The outer core also has cyclones or whirlpools powered by the Coriolis effects of Earth’s rotation. These complex and unpredictable motions generate the fluctuating magnetic field. The outer core is seething, swirling, and turbulent, which has been detected by the constant changes and reversals in polarity throughout the planet’s history. Further, iron has a special characteristic.When it is hotter than 1043 K, its Curie temperature, iron loses its magnetic properties. Therefore the Earth’s magnetic field is caused not by magnetised iron deposits, but mostly by electric currents in the liquid outer core.Q.Which of the following statements about the Earth’s core was implied by Scientist 2?a)The Earth’s inner core is a rotating mass of iron.b)The Earth’s inner core is solely responsible for the magnetic field.c)The Earth’s core is iron and possesses properties similar to a bar magnet.d)The Earth’s core has a temperature above 1043 K.Correct answer is option 'D'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of Directions:Read the passages and choose the best answer to each question.PassageThe Earth’s magnetic field is one of its most significant natural phenomena. For centuries, the field has been used to aid navigation and exploration, and has been vital to many major discoveries. The magnetic field of the Earth extends several thousands of miles into space. It has the effect of shielding the Earth from solar wind, protecting the planet from dangerous high-energy particles and radiation. The exact source of the Earth’s magnetic field is not certain. The following two Scientists attempt to explain the phenomenon.Scientist 1The Earth’s magnetic field is similar to that of a bar magnet tilted 11 degrees from the spin axis of the Earth.The magnetic field of a bar magnet, or any other type of permanent magnet, is created by the coordinated motions of electrons within iron atoms. It is widely accepted that the Earth’s core consists of metals. The inner core is 70% as wide as the moon and consists of a solid iron ball, which would exhibit properties of ferromagnetism (the natural magnetic tendency of iron). The core has its own rotation and is surrounded by a “sea” of molten rock. The magnetic field grows and wanes, and the Earth’s poles drift and occasionally flip as the rotation of the core changes. The poles of the magnetic field have “flipped” many times due to the fluctuations in the rotation of the solid inner core. Other fluctuations in the magnetic field that can occur on a daily basis are largely the result of interference by solar wind.Scientist 2The Earth’s magnetic field is attributed to a dynamo effect of circulating electric current in the molten outer core. Electric currents cause magnetic fields; therefore, the circulating electric currents in the Earth’s molten metallic core are the origin of the magnetic field. When conducting fluid flows across an existing magnetic field, electric currents are induced, creating another magnetic field. When this magnetic field reinforces the original magnetic field, a dynamo is created which sustains itself.Sitting atop the hot, iron inner core, the Earth’s molten outer core churns and moves. The outer core also has cyclones or whirlpools powered by the Coriolis effects of Earth’s rotation. These complex and unpredictable motions generate the fluctuating magnetic field. The outer core is seething, swirling, and turbulent, which has been detected by the constant changes and reversals in polarity throughout the planet’s history. Further, iron has a special characteristic.When it is hotter than 1043 K, its Curie temperature, iron loses its magnetic properties. Therefore the Earth’s magnetic field is caused not by magnetised iron deposits, but mostly by electric currents in the liquid outer core.Q.Which of the following statements about the Earth’s core was implied by Scientist 2?a)The Earth’s inner core is a rotating mass of iron.b)The Earth’s inner core is solely responsible for the magnetic field.c)The Earth’s core is iron and possesses properties similar to a bar magnet.d)The Earth’s core has a temperature above 1043 K.Correct answer is option 'D'. Can you explain this answer?, a detailed solution for Directions:Read the passages and choose the best answer to each question.PassageThe Earth’s magnetic field is one of its most significant natural phenomena. For centuries, the field has been used to aid navigation and exploration, and has been vital to many major discoveries. The magnetic field of the Earth extends several thousands of miles into space. It has the effect of shielding the Earth from solar wind, protecting the planet from dangerous high-energy particles and radiation. The exact source of the Earth’s magnetic field is not certain. The following two Scientists attempt to explain the phenomenon.Scientist 1The Earth’s magnetic field is similar to that of a bar magnet tilted 11 degrees from the spin axis of the Earth.The magnetic field of a bar magnet, or any other type of permanent magnet, is created by the coordinated motions of electrons within iron atoms. It is widely accepted that the Earth’s core consists of metals. The inner core is 70% as wide as the moon and consists of a solid iron ball, which would exhibit properties of ferromagnetism (the natural magnetic tendency of iron). The core has its own rotation and is surrounded by a “sea” of molten rock. The magnetic field grows and wanes, and the Earth’s poles drift and occasionally flip as the rotation of the core changes. The poles of the magnetic field have “flipped” many times due to the fluctuations in the rotation of the solid inner core. Other fluctuations in the magnetic field that can occur on a daily basis are largely the result of interference by solar wind.Scientist 2The Earth’s magnetic field is attributed to a dynamo effect of circulating electric current in the molten outer core. Electric currents cause magnetic fields; therefore, the circulating electric currents in the Earth’s molten metallic core are the origin of the magnetic field. When conducting fluid flows across an existing magnetic field, electric currents are induced, creating another magnetic field. When this magnetic field reinforces the original magnetic field, a dynamo is created which sustains itself.Sitting atop the hot, iron inner core, the Earth’s molten outer core churns and moves. The outer core also has cyclones or whirlpools powered by the Coriolis effects of Earth’s rotation. These complex and unpredictable motions generate the fluctuating magnetic field. The outer core is seething, swirling, and turbulent, which has been detected by the constant changes and reversals in polarity throughout the planet’s history. Further, iron has a special characteristic.When it is hotter than 1043 K, its Curie temperature, iron loses its magnetic properties. Therefore the Earth’s magnetic field is caused not by magnetised iron deposits, but mostly by electric currents in the liquid outer core.Q.Which of the following statements about the Earth’s core was implied by Scientist 2?a)The Earth’s inner core is a rotating mass of iron.b)The Earth’s inner core is solely responsible for the magnetic field.c)The Earth’s core is iron and possesses properties similar to a bar magnet.d)The Earth’s core has a temperature above 1043 K.Correct answer is option 'D'. Can you explain this answer? has been provided alongside types of Directions:Read the passages and choose the best answer to each question.PassageThe Earth’s magnetic field is one of its most significant natural phenomena. For centuries, the field has been used to aid navigation and exploration, and has been vital to many major discoveries. The magnetic field of the Earth extends several thousands of miles into space. It has the effect of shielding the Earth from solar wind, protecting the planet from dangerous high-energy particles and radiation. The exact source of the Earth’s magnetic field is not certain. The following two Scientists attempt to explain the phenomenon.Scientist 1The Earth’s magnetic field is similar to that of a bar magnet tilted 11 degrees from the spin axis of the Earth.The magnetic field of a bar magnet, or any other type of permanent magnet, is created by the coordinated motions of electrons within iron atoms. It is widely accepted that the Earth’s core consists of metals. The inner core is 70% as wide as the moon and consists of a solid iron ball, which would exhibit properties of ferromagnetism (the natural magnetic tendency of iron). The core has its own rotation and is surrounded by a “sea” of molten rock. The magnetic field grows and wanes, and the Earth’s poles drift and occasionally flip as the rotation of the core changes. The poles of the magnetic field have “flipped” many times due to the fluctuations in the rotation of the solid inner core. Other fluctuations in the magnetic field that can occur on a daily basis are largely the result of interference by solar wind.Scientist 2The Earth’s magnetic field is attributed to a dynamo effect of circulating electric current in the molten outer core. Electric currents cause magnetic fields; therefore, the circulating electric currents in the Earth’s molten metallic core are the origin of the magnetic field. When conducting fluid flows across an existing magnetic field, electric currents are induced, creating another magnetic field. When this magnetic field reinforces the original magnetic field, a dynamo is created which sustains itself.Sitting atop the hot, iron inner core, the Earth’s molten outer core churns and moves. The outer core also has cyclones or whirlpools powered by the Coriolis effects of Earth’s rotation. These complex and unpredictable motions generate the fluctuating magnetic field. The outer core is seething, swirling, and turbulent, which has been detected by the constant changes and reversals in polarity throughout the planet’s history. Further, iron has a special characteristic.When it is hotter than 1043 K, its Curie temperature, iron loses its magnetic properties. Therefore the Earth’s magnetic field is caused not by magnetised iron deposits, but mostly by electric currents in the liquid outer core.Q.Which of the following statements about the Earth’s core was implied by Scientist 2?a)The Earth’s inner core is a rotating mass of iron.b)The Earth’s inner core is solely responsible for the magnetic field.c)The Earth’s core is iron and possesses properties similar to a bar magnet.d)The Earth’s core has a temperature above 1043 K.Correct answer is option 'D'. Can you explain this answer? theory, EduRev gives you an ample number of questions to practice Directions:Read the passages and choose the best answer to each question.PassageThe Earth’s magnetic field is one of its most significant natural phenomena. For centuries, the field has been used to aid navigation and exploration, and has been vital to many major discoveries. The magnetic field of the Earth extends several thousands of miles into space. It has the effect of shielding the Earth from solar wind, protecting the planet from dangerous high-energy particles and radiation. The exact source of the Earth’s magnetic field is not certain. The following two Scientists attempt to explain the phenomenon.Scientist 1The Earth’s magnetic field is similar to that of a bar magnet tilted 11 degrees from the spin axis of the Earth.The magnetic field of a bar magnet, or any other type of permanent magnet, is created by the coordinated motions of electrons within iron atoms. It is widely accepted that the Earth’s core consists of metals. The inner core is 70% as wide as the moon and consists of a solid iron ball, which would exhibit properties of ferromagnetism (the natural magnetic tendency of iron). The core has its own rotation and is surrounded by a “sea” of molten rock. The magnetic field grows and wanes, and the Earth’s poles drift and occasionally flip as the rotation of the core changes. The poles of the magnetic field have “flipped” many times due to the fluctuations in the rotation of the solid inner core. Other fluctuations in the magnetic field that can occur on a daily basis are largely the result of interference by solar wind.Scientist 2The Earth’s magnetic field is attributed to a dynamo effect of circulating electric current in the molten outer core. Electric currents cause magnetic fields; therefore, the circulating electric currents in the Earth’s molten metallic core are the origin of the magnetic field. When conducting fluid flows across an existing magnetic field, electric currents are induced, creating another magnetic field. When this magnetic field reinforces the original magnetic field, a dynamo is created which sustains itself.Sitting atop the hot, iron inner core, the Earth’s molten outer core churns and moves. The outer core also has cyclones or whirlpools powered by the Coriolis effects of Earth’s rotation. These complex and unpredictable motions generate the fluctuating magnetic field. The outer core is seething, swirling, and turbulent, which has been detected by the constant changes and reversals in polarity throughout the planet’s history. Further, iron has a special characteristic.When it is hotter than 1043 K, its Curie temperature, iron loses its magnetic properties. Therefore the Earth’s magnetic field is caused not by magnetised iron deposits, but mostly by electric currents in the liquid outer core.Q.Which of the following statements about the Earth’s core was implied by Scientist 2?a)The Earth’s inner core is a rotating mass of iron.b)The Earth’s inner core is solely responsible for the magnetic field.c)The Earth’s core is iron and possesses properties similar to a bar magnet.d)The Earth’s core has a temperature above 1043 K.Correct answer is option 'D'. Can you explain this answer? tests, examples and also practice ACT tests.
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