1. 6.28×10⁻⁴ T 2. 3.14×10⁻⁴ T 3. 6.28×10⁻⁵ T 4. 3.14×10⁻⁵ T

Answer: 1. 6.28×10⁻⁴ T Field inside a long solenoid: B=μ₀nI , with n turns per metre. n=100/0.5=200\ m⁻¹ B=4π×10⁻⁷×200×2.5=6.28×10⁻⁴\ T Answer: option 1.

Topic: Ampere's law: straight wire and solenoid· Magnetic Effects of Current and Magnetism

A long solenoid of 50 cm length having 100 turns carries a current of 2.5 A. The magnetic field at the centre of the solenoid is :(μ_0 = 4π×10^-7 T m A^-1)

1. $6.28\times10^{-4}$ T

2. $3.14\times10^{-4}$ T

3. $6.28\times10^{-5}$ T

4. $3.14\times10^{-5}$ T

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Answer: 1. $6.28\times10^{-4}$ T

Field inside a long solenoid: $B=\mu_0nI$, with $n$ turns per metre.

$n=\dfrac{100}{0.5}=200\ \text{m}^{-1}$

$$B=4\pi\times10^{-7}\times200\times2.5=6.28\times10^{-4}\ \text{T}$$

Answer: option 1.

Doubtly AI · 30 Oct 2026 AI-generated · not yet verified Report

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A long solenoid of 50 cm length having 100 turns carries a current of 2.5 A. The magnetic field at the centre of the solenoid is :(μ_0 = 4π×10^-7 T m A^-1)

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