Question

The space inside a straight current carrying solenoid is filled with a magnetic material having magnetic susceptibility equal to $1.2 \times 10^{–5}$. What is fractional increase in the magnetic field inside solenoid with respect to air as medium inside the solenoid?

• A. $1.2 \times 10^{–5}$
• B. $1.2 \times 10^{–3}$
• C. $1.8 \times 10^{–3}$
• D. $2.4 \times 10^{–5}$

Answer 1

Answer: (A)

$1.2 \times 10^{–5}$

Answer 2

$\vec{B'}$=$µ0(1-X)ni$ in the material
$\vec{B}$=µ0$ni$ without material

So, fractional increase is
$\frac{B'-B}{B} =X =1.2 × 10^{-5}$

So, the correct option is (A): $1.2 \times 10^{–5}$