Q. The angle of dip at a place is $37{^\circ}$ and the vertical component of the earth’s magnetic field is $6 \times 10^{- 5}\ T.$ The earth’s magnetic field at this place is $(tan\ 37{^\circ} = 3/4$)
A) $7 \times 10^{- 5}\ T$
B) $6 \times 10^{- 5}\ T$
C) $5 \times 10^{- 5}\ T$
D) $10^{- 4}\ T$
Explanation
(d) Given $\tan{37{^\circ} = \frac{3}{4}}$
The vertical component of the earth’s magnetic field
$\ \ \ \ \ \ \ \ B_{H} = 6 \times 10^{- 5}\ T$
$\sin{37{^\circ} = \frac{3}{5}}$
For vertical component
$\ \ \ \ B_{H} = B\sin\theta$
$\ or\ B = \frac{B_{H}}{\sin\theta}$
or $\ B = \frac{2\ \times {\ 10}^{- 5}}{5} \times 5$
$or\ \ B = 10 \times 10^{- 5}$
or $B = 10^{- 4}$ T
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.