NEET2026PhysicsChapterActual
A steady current of 10 A is flowing through a wire which is bent into the shape of a circular arc of radius 5 cm . If the arc subtends an angle of 90^ at its centre, what is the magnitude of the magnetic field produced at the centre of the arc? (Assume permeability of free space, ₀ = 4 10⁻⁷ T m/A )
Options
- A2 10⁻⁵ T
- B10⁻⁵ T
- C4 10⁻⁵ T
- D8 10⁻⁵ T
Correct answer
B. 10⁻⁵ T
Step-by-step solution
The magnetic field at the centre of a circular arc subtending an angle is given by B = ₀ I 4 r . Given I = 10 A , r = 5 cm = 0.05 m , and = 90^ = 2 radians. Substituting the values: B = 4 10⁻⁷ 10 4 0.05 2 B = 10⁻⁶ 0.05 2 B = 10⁻⁶ 0.1 B = 10⁻⁵ T Answer: 10⁻⁵ T