JEE Main2006PhysicsMagnetic Effects of CurrentActual
A long solenoid has 200 turns per cm and carries a current i . The magnetic field at its centre is 6.28 10⁻² Weber / m ^2 . Another long solenoid has 100 turns per cm and it carries a current i / 3 . The value of the magnetic field at its centre is
Options
- A1.05 10⁻⁴ Weber/m
- B1.05 10⁻² Weber / m ^2
- C1.05 10⁻⁵ Weber / m ^2
- D1.05 10⁻³ Weber / m ^2
Correct answer
B. 1.05 10⁻² Weber / m ^2
Step-by-step solution
B₂= B₁ n₂ i₂ n₁ i₁ = (6.28 10⁻² )(100 i / 3) 200(i) =1.05 10⁻² ~W / m ^2