A solenoid of length 0.5 m has a radius of 1 cm and is made up of 'm' number of turns. It carries a current of 5A. If the magnitude of the magnetic field inside the solenoid is 6.28 × 10⁻³ T, then the value of m is :
Physics · Magnetic effect of current · ampere's law and its application
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Question

A solenoid of length 0.5 m has a radius of 1 cm and is made up of 'm' number of turns. It carries a current of 5A. If the magnitude of the magnetic field inside the solenoid is 6.28 × 10⁻³ T, then the value of m is :

Physics · Magnetic effect of current · ampere's law and its application

G1 Physics · Accepted Answer

Magnetic field inside a long solenoid: B = μ₀nI where: n = m/ℓ Therefore: B = μ₀(m/ℓ)I So: m = Bℓ/(μ₀I) = [6.28 × 10⁻³ × 0.5]/[4π × 10⁻⁷ × 5] ≈ 500