Question

Find the magnetic field due to a current carrying wire at point P. (a =7 cm)

• A. $2\times {10}^{-7}$ Tesla
• B. $3\times {10}^{-7}$ Tesla
• C. ${10}^{-5}$ Tesla
• D. $7\times {10}^{-5}$ Tesla

Answer 1

The correct option is C ${10}^{-5}$ Tesla


$B=\frac{{\mu }_{0}i}{4\pi a}(sin\alpha +sin\beta )$
$=\frac{{10}^{-7}\times 5}{7\times {10}^{-2}}(sin\alpha +sin\beta )=\frac{5}{7}\times {10}^{-5}\{\frac{4}{5}+\frac{3}{5}\}=\frac{7}{5}\times \frac{5}{7}\times {10}^{-5}$
$={10}^{-5}$ T