In a solenoid, the current flowing through the wire is / and number of turns per unit length is n. This gives a magnetic field B inside the solenoid. If number of tuni per unit length is increased to 2/j, what will be the value of magnetic field in the so

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Q: 37 (NDA-I/2017)
In a solenoid, the current flowing through the wire is / and number of turns per unit length is n. This gives a magnetic field B inside the solenoid. If number of tuni per unit length is increased to 2/j, what will be the value of magnetic field in the solenoid ?

question_subject: 

Science

question_exam: 

NDA-I

stats: 

0,4,4,1,4,2,1

keywords: 

{'magnetic field': [0, 0, 0, 6], 'solenoid': [0, 0, 0, 1], 'current': [0, 0, 0, 3], 'unit length': [0, 0, 0, 1], 'value': [0, 0, 1, 0], 'bia': [0, 0, 0, 1], 'bi2': [0, 0, 0, 1], 'wire': [0, 0, 7, 16], 'tuni': [0, 0, 0, 1], 'number': [0, 0, 0, 2]}

In a solenoid, the magnetic field inside the solenoid is directly proportional to the current flowing through the wire and the number of turns per unit length of the solenoid.

Option 1: B - This option suggests that the magnetic field will remain unchanged. However, as the number of turns per unit length is increasing, this option is unlikely to be correct.

Option 2: IB - This option suggests that the magnetic field will be multiplied by the current flowing through the wire. Since the current is represented by I, this option is correct.

Option 3: BI2 - This option suggests that the magnetic field will be multiplied by the square of the current flowing through the wire. However, the correct representation for this would be I^2, so this option is not correct.

Option 4: BiA - This option suggests that the magnetic field will be multiplied by the current and a variable A. Since the variable A is not mentioned in the question or explanation, this option is not meaningful.

Therefore, the correct answer is option 2: IB. Increasing the number of turns per unit length in a solenoid will increase the magnetic field inside the solenoid, and the new magnetic field value will be equal to the original magnetic field