MHT CET202312 May 2023Evening ShiftPhysicsMagnetic Effects of CurrentActual
Two concentric circular coils of 10 turns each are situated in the same plane. Their radii are 20 ~cm and 40 ~cm and they carry respectively 0.2 ~A and 0.3 ~A current in opposite direction. The magnetic field at the centre is ( ₀=4 10⁻⁷ SI units)
Options
- A4 10⁻⁷ ~T
- B5 10⁻⁷ ~T
- C2 10⁻⁵ ~T
- D7 10⁻⁶ ~T
Correct answer
B. 5 10⁻⁷ ~T
Step-by-step solution
aligned B _ net & = ₀ n ₁ I ₁ 2 r ₁ - ₀ n ₂ I ₂ 2 r ₂ & = 10 ₀ 2 [ 0.2 0.2 - 0.3 0.4 ] & =5 4 10⁻⁷ 0.25 & =5 10⁻⁷ ~T aligned