Question

At a certain place, the angle of dip is ${30}^o$ and the horizontal component of earth's magnetic field is $0.5$ oersted. The earth total magnetic field is( in oersted)

• A. $\sqrt{3}$
• B. $1$
• C. $\frac{1}{\sqrt{3}}$
• D. $\frac{1}{2}$

Answer 1

Answer: (C)

$\frac{1}{\sqrt{3}}$

$H=0.5$
$I\cos {30}^o=H$
$I=\frac{2}{\sqrt{3}}H$
$I=\frac{1}{2}\times \frac{2}{\sqrt{3}}$
$I=\frac{1}{\sqrt{3}}$