Question

A dip circle is set such that the dip needle moves freely in the magnetic meridian. In this position, the angle of dip is 39${}^0$. Now the dip circle is rotated so that the plane in which the needle moves makes an angle of 30${}^0$ with the magnetic meridian. In this position ,the needle will dip by an angle :

• A. exactly 39${}^0$
• B. 30${}^0$
• C. more than 39${}^0$
• D. less than 39${}^0$

Answer 1

Answer: (C)

more than 39${}^0$

The relation between true dip and the apparent dip is given by
$tan{\delta }_a=\frac{tan{\delta }_t}{cos\theta }$
$tan{\delta }_a=tan{39}^o\times 1.15$
Therefore ${\delta }_a$ i.e , the apparent dip angle value increases