Question

A long solenoid has 800 turns per meter length of solenoid. A current of $1.6A$ flows through it. The magnetic induction at the end of the solenoid on its axis is

• A. $16\times {10}^{-4}$ tesla
• B. $8\times {10}^{-4}$ tesla
• C. $32\times {10}^{-4}$ tesla
• D. $4\times {10}^{-4}$ tesla

Answer 1

Answer: (B)

$8\times {10}^{-4}$ tesla

$Given:$ n = 800 turns/meter

Currrent ( $I$ ) = 1.6A

$Solution:$ The magnetic induction at the middle point of solenoid on its axis is given as,

$B$ = $\frac{{\mu }_{o}nI}{2}$

= $\frac{4\pi \times {10}^{-7}\times 800\times 1.6}{2}$

= $8.04$ $\times {10}^{-4}$ $T$

Hence,The magnetic induction at the end of the solenoid on its axis is $8.04$ $\times {10}^{-4}$ $T$

$So,the$ $correct$ $option:B$