Answer & explanation
Correct answer: option 1
$\text{The earth's magnetic field is B and its horizontal and vertical components are } B_h and B_v \text{ respectively}$
$ cos 60^o = \frac{B_h}{B}$
$\Rightarrow B =2B_h = 0.50G$
Correct answer: option 1
$\text{The earth's magnetic field is B and its horizontal and vertical components are } B_h and B_v \text{ respectively}$
$ cos 60^o = \frac{B_h}{B}$
$\Rightarrow B =2B_h = 0.50G$