AP EAMCET20226 Jul 2022Morning ShiftPhysicsMagnetic Effects of CurrentActual
A long current carrying wire produces a magnetic field of 1 T at a distance of r . The magnetic field (a) r 2 (b) 2 r and (c) 3 r is
Options
- A(a) 2 ~T ,( ~b )= 1 2 ~T ,( c )= 1 3 ~T
- B(a) 3 ~T ,( ~b )= 1 3 ~T ,( c )= 1 6 ~T
- C(a) 3 2 ~T ,( ~b )= 1 4 ~T ,( c )= 1 8 ~T
- D(a) 5 2 ~T , ( . b) = 1 2 ~T ,( c )= 1 3 ~T
Correct answer
A. (a) 2 ~T ,( ~b )= 1 2 ~T ,( c )= 1 3 ~T
Step-by-step solution
For a long straight wire B= ₀ i 2 r B 1 r B _ r / 2 ~B _ r = r r 2 B _ r / 2 ~B _ r =2 B _ r / 2 =2 1=2 ~T Similarly, B _ 2 r = 1 2 ~T and B _ 3 r = 1 3 ~T