NEETPhysicsMagnetic Effects of Current
Match List-I with List-II regarding the magnetic field B at a distance r from the axis of a long straight current-carrying conductor (where R is the radius of the conductor). List-I List-II (A) Inside a solid cylinder ( r (I) B = 0 (B) Outside a solid cylinder ( r > R ) (II) B 1 r (C) Inside a thin-walled hollow cylinder ( r (III) B r (D) Outside a thin-walled hollow cylinder ( r > R ) (IV) B 1 r^2 Choose the correct
Options
- A(A)-(II), (B)-(III), (C)-(I), (D)-(II)
- B(A)-(III), (B)-(IV), (C)-(I), (D)-(IV)
- C(A)-(III), (B)-(II), (C)-(I), (D)-(II)
- D(A)-(III), (B)-(II), (C)-(III), (D)-(II)
Correct answer
C. (A)-(III), (B)-(II), (C)-(I), (D)-(II)
Step-by-step solution
According to Ampere's circuital law: For a solid current-carrying cylinder of radius R : Inside ( r Outside ( r > R ): B = ₀ I 2 r , which means B 1 r . So, (B) matches with (II). For a thin-walled hollow current-carrying cylinder of radius R : Inside ( r Outside ( r > R ): The cylinder behaves like a line current, B = ₀ I 2 r , which means B 1 r . So, (D) matches with (II). Therefore, the correct matching is (A)-(III), (B)-(II), (C)-(I), (D)-(II). Answer: (A)-(III), (B)-(II), (C)-(I), (D)-(II)