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A piece of copper and another of germanium are cooled from room temperature to 80 K. The resistance of
- a)copper decreases and that of germanium increases
- b)each of them increases
- c)each of them decreases
- d)copper increases and that of germanium decreases
Correct answer is option 'A'. Can you explain this answer?
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Verified Answer
A piece of copper and another of germanium are cooled from room temper...
We know, a piece of copper is a metal while that of germanium is a semiconducting material. For metals resistance increases with increase in temperature. The semiconductor has a negative temperature coefficient of resistance. Hence, when it is cooled its resistance increases.
Most Upvoted Answer
A piece of copper and another of germanium are cooled from room temper...
Explanation:
When a material is cooled down, its resistance can change due to the behavior of its electrons. In the case of copper and germanium, the behavior of electrons is different, leading to opposite changes in resistance.
Copper:
- Copper is a metal, and metals generally have a positive temperature coefficient of resistance. This means that as the temperature decreases, the resistance of copper decreases as well.
- At higher temperatures, the atoms in copper vibrate more vigorously, causing more collisions with the flowing electrons. These collisions impede the flow of electrons and increase the resistance.
- As the temperature decreases, the vibrations of the atoms also decrease, resulting in fewer collisions and a decrease in resistance.
Germanium:
- Germanium is a semiconductor, and semiconductors generally have a negative temperature coefficient of resistance. This means that as the temperature decreases, the resistance of germanium increases.
- In a semiconductor, the resistance is primarily determined by the number of free charge carriers (electrons or holes) available for conduction.
- At higher temperatures, more charge carriers are available due to increased thermal energy, leading to a lower resistance.
- As the temperature decreases, the number of charge carriers decreases, resulting in fewer available carriers for conduction and an increase in resistance.
Conclusion:
In summary, when a piece of copper is cooled from room temperature to 80 K, its resistance decreases due to the decrease in atomic vibrations. On the other hand, when a piece of germanium is cooled, its resistance increases due to the decrease in the number of available charge carriers. Therefore, the correct answer is option 'A' - the resistance of copper decreases and that of germanium increases.
When a material is cooled down, its resistance can change due to the behavior of its electrons. In the case of copper and germanium, the behavior of electrons is different, leading to opposite changes in resistance.
Copper:
- Copper is a metal, and metals generally have a positive temperature coefficient of resistance. This means that as the temperature decreases, the resistance of copper decreases as well.
- At higher temperatures, the atoms in copper vibrate more vigorously, causing more collisions with the flowing electrons. These collisions impede the flow of electrons and increase the resistance.
- As the temperature decreases, the vibrations of the atoms also decrease, resulting in fewer collisions and a decrease in resistance.
Germanium:
- Germanium is a semiconductor, and semiconductors generally have a negative temperature coefficient of resistance. This means that as the temperature decreases, the resistance of germanium increases.
- In a semiconductor, the resistance is primarily determined by the number of free charge carriers (electrons or holes) available for conduction.
- At higher temperatures, more charge carriers are available due to increased thermal energy, leading to a lower resistance.
- As the temperature decreases, the number of charge carriers decreases, resulting in fewer available carriers for conduction and an increase in resistance.
Conclusion:
In summary, when a piece of copper is cooled from room temperature to 80 K, its resistance decreases due to the decrease in atomic vibrations. On the other hand, when a piece of germanium is cooled, its resistance increases due to the decrease in the number of available charge carriers. Therefore, the correct answer is option 'A' - the resistance of copper decreases and that of germanium increases.
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A piece of copper and another of germanium are cooled from room temperature to 80 K. The resistance ofa)copper decreases and that of germanium increasesb)each of them increasesc)each of them decreasesd)copper increases and that of germanium decreasesCorrect answer is option 'A'. Can you explain this answer?
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A piece of copper and another of germanium are cooled from room temperature to 80 K. The resistance ofa)copper decreases and that of germanium increasesb)each of them increasesc)each of them decreasesd)copper increases and that of germanium decreasesCorrect answer is option 'A'. Can you explain this answer? for JEE 2024 is part of JEE preparation. The Question and answers have been prepared according to the JEE exam syllabus. Information about A piece of copper and another of germanium are cooled from room temperature to 80 K. The resistance ofa)copper decreases and that of germanium increasesb)each of them increasesc)each of them decreasesd)copper increases and that of germanium decreasesCorrect answer is option 'A'. Can you explain this answer? covers all topics & solutions for JEE 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for A piece of copper and another of germanium are cooled from room temperature to 80 K. The resistance ofa)copper decreases and that of germanium increasesb)each of them increasesc)each of them decreasesd)copper increases and that of germanium decreasesCorrect answer is option 'A'. Can you explain this answer?.
A piece of copper and another of germanium are cooled from room temperature to 80 K. The resistance ofa)copper decreases and that of germanium increasesb)each of them increasesc)each of them decreasesd)copper increases and that of germanium decreasesCorrect answer is option 'A'. Can you explain this answer? for JEE 2024 is part of JEE preparation. The Question and answers have been prepared according to the JEE exam syllabus. Information about A piece of copper and another of germanium are cooled from room temperature to 80 K. The resistance ofa)copper decreases and that of germanium increasesb)each of them increasesc)each of them decreasesd)copper increases and that of germanium decreasesCorrect answer is option 'A'. Can you explain this answer? covers all topics & solutions for JEE 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for A piece of copper and another of germanium are cooled from room temperature to 80 K. The resistance ofa)copper decreases and that of germanium increasesb)each of them increasesc)each of them decreasesd)copper increases and that of germanium decreasesCorrect answer is option 'A'. Can you explain this answer?.
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A piece of copper and another of germanium are cooled from room temperature to 80 K. The resistance ofa)copper decreases and that of germanium increasesb)each of them increasesc)each of them decreasesd)copper increases and that of germanium decreasesCorrect answer is option 'A'. Can you explain this answer?, a detailed solution for A piece of copper and another of germanium are cooled from room temperature to 80 K. The resistance ofa)copper decreases and that of germanium increasesb)each of them increasesc)each of them decreasesd)copper increases and that of germanium decreasesCorrect answer is option 'A'. Can you explain this answer? has been provided alongside types of A piece of copper and another of germanium are cooled from room temperature to 80 K. The resistance ofa)copper decreases and that of germanium increasesb)each of them increasesc)each of them decreasesd)copper increases and that of germanium decreasesCorrect answer is option 'A'. Can you explain this answer? theory, EduRev gives you an
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