If length of solenoid gets doubled while keeping N (number of turns) constant, the resultant magnetic field will be?
Correct answer: A. B/2
- A. B/2
- B. B/4
- C. 2B
- D. B/3
Explanation
The magnetic field inside a solenoid is given by: B = μ₀ * n * Iwhere:B is the magnetic fieldμ₀ is the permeability of free spacen is the number of turns per unit lengthI is the currentIn this case, the number of turns (N) is constant, and the length (l) is doubled. This means the number of turns per unit length (n = N/l) is halved. Therefore, the magnetic field (B) will also be halved.
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