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A wire of length l is in the form of a circular loop having one turn only. The loop is carrying a current I and induces a magnetic field of strength B1 at the centre of the loop. If the same wire is used to make a coil having two turns, then the strength of the magnetic field at the centre is B2 providing the current flowing the loop is same. The correct option is

  • a)
    B2 = 2B1

  • b)
    2B2 = B1

  • c)
    B2 = 4B1

  • d)
    4B2 = B1

Correct answer is option 'C'. Can you explain this answer?
Most Upvoted Answer
A wire of length l is in the form of a circular loop having one turn o...
Explanation:

Given, a wire of length l is in the form of a circular loop having one turn only. The loop is carrying a current I and induces a magnetic field of strength B1 at the centre of the loop.

We need to find the strength of the magnetic field at the centre if the same wire is used to make a coil having two turns.

Formula:

The magnetic field at the centre of a circular loop of radius R carrying current I is given by:

B1 = μ0I/2R

Calculation:

For the given single turn loop,

B1 = μ0I/2R

For two turns, the current I will be the same, but the radius of the loop will be doubled.

So, the new radius will be 2R.

Therefore, the magnetic field at the centre of the loop with two turns is given by:

B2 = μ0I/2(2R) = μ0I/4R

Comparing B2 with B1, we get:

B2/B1 = (μ0I/4R)/(μ0I/2R) = 1/2

Therefore, B2 = 1/2 B1

Final Answer:

Hence, the correct option is c) B2 = 4B1.
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Community Answer
A wire of length l is in the form of a circular loop having one turn o...
For the loop carrying current, magnetic field at the centre is given by 

For N = 1 and r = r1 

Also, the length of the wire is same.
Therefore,

This is our required solution.
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Question Description
A wire of length l is in the form of a circular loop having one turn only. The loop is carrying a current I and induces a magnetic field of strength B1 at the centre of the loop. If the same wire is used to make a coil having two turns, then the strength of the magnetic field at the centre is B2 providing the current flowing the loop is same. The correct option isa)B2 = 2B1b)2B2 = B1c)B2 = 4B1d)4B2 = B1Correct answer is option 'C'. Can you explain this answer? for JEE 2025 is part of JEE preparation. The Question and answers have been prepared according to the JEE exam syllabus. Information about A wire of length l is in the form of a circular loop having one turn only. The loop is carrying a current I and induces a magnetic field of strength B1 at the centre of the loop. If the same wire is used to make a coil having two turns, then the strength of the magnetic field at the centre is B2 providing the current flowing the loop is same. The correct option isa)B2 = 2B1b)2B2 = B1c)B2 = 4B1d)4B2 = B1Correct answer is option 'C'. Can you explain this answer? covers all topics & solutions for JEE 2025 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for A wire of length l is in the form of a circular loop having one turn only. The loop is carrying a current I and induces a magnetic field of strength B1 at the centre of the loop. If the same wire is used to make a coil having two turns, then the strength of the magnetic field at the centre is B2 providing the current flowing the loop is same. The correct option isa)B2 = 2B1b)2B2 = B1c)B2 = 4B1d)4B2 = B1Correct answer is option 'C'. Can you explain this answer?.
Solutions for A wire of length l is in the form of a circular loop having one turn only. The loop is carrying a current I and induces a magnetic field of strength B1 at the centre of the loop. If the same wire is used to make a coil having two turns, then the strength of the magnetic field at the centre is B2 providing the current flowing the loop is same. The correct option isa)B2 = 2B1b)2B2 = B1c)B2 = 4B1d)4B2 = B1Correct answer is option 'C'. Can you explain this answer? in English & in Hindi are available as part of our courses for JEE. Download more important topics, notes, lectures and mock test series for JEE Exam by signing up for free.
Here you can find the meaning of A wire of length l is in the form of a circular loop having one turn only. The loop is carrying a current I and induces a magnetic field of strength B1 at the centre of the loop. If the same wire is used to make a coil having two turns, then the strength of the magnetic field at the centre is B2 providing the current flowing the loop is same. The correct option isa)B2 = 2B1b)2B2 = B1c)B2 = 4B1d)4B2 = B1Correct answer is option 'C'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of A wire of length l is in the form of a circular loop having one turn only. The loop is carrying a current I and induces a magnetic field of strength B1 at the centre of the loop. If the same wire is used to make a coil having two turns, then the strength of the magnetic field at the centre is B2 providing the current flowing the loop is same. The correct option isa)B2 = 2B1b)2B2 = B1c)B2 = 4B1d)4B2 = B1Correct answer is option 'C'. Can you explain this answer?, a detailed solution for A wire of length l is in the form of a circular loop having one turn only. The loop is carrying a current I and induces a magnetic field of strength B1 at the centre of the loop. If the same wire is used to make a coil having two turns, then the strength of the magnetic field at the centre is B2 providing the current flowing the loop is same. The correct option isa)B2 = 2B1b)2B2 = B1c)B2 = 4B1d)4B2 = B1Correct answer is option 'C'. Can you explain this answer? has been provided alongside types of A wire of length l is in the form of a circular loop having one turn only. The loop is carrying a current I and induces a magnetic field of strength B1 at the centre of the loop. If the same wire is used to make a coil having two turns, then the strength of the magnetic field at the centre is B2 providing the current flowing the loop is same. The correct option isa)B2 = 2B1b)2B2 = B1c)B2 = 4B1d)4B2 = B1Correct answer is option 'C'. Can you explain this answer? theory, EduRev gives you an ample number of questions to practice A wire of length l is in the form of a circular loop having one turn only. The loop is carrying a current I and induces a magnetic field of strength B1 at the centre of the loop. If the same wire is used to make a coil having two turns, then the strength of the magnetic field at the centre is B2 providing the current flowing the loop is same. The correct option isa)B2 = 2B1b)2B2 = B1c)B2 = 4B1d)4B2 = B1Correct answer is option 'C'. Can you explain this answer? tests, examples and also practice JEE tests.
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