A straight long wire is carrying current I. The ratio of magnetic field due to this wire at perpendicular distance 2 cm and 5 cm respectively from the wire is

Step-by-step solution

The magnetic field due to a long straight wire carrying current I at a perpendicular distance r is given by B = ₀ I 2 r . This implies that B 1 r . Given r₁ = 2 cm and r₂ = 5 cm . The ratio of the magnetic fields is B₁ B₂ = r₂ r₁ = 5 2 . Thus, the required ratio is 5:2 . Answer: 5:2