A telephone cable at a place has four long straight horizontal wires carrying a current of 1.0 A in the same direction east to west. The earth's magnetic field at the place is 0.39 G, and the angle of dip is 35°. The magnetic declination is nearly zero. What are the resultant magnetic fields at points 4.0 cm below the cable ?

Options

A. at P `ox` and at Q `o.`
B. at P `o.` and at Q `ox`
C. at P `ox` and at Q `ox`
D. at P `o.` and at Q `o.`

Answer

A

Explanation

At P `ox` and at Q `o.`
(Here `ox` means perpendicularly inside the plane of figure and `o.` means perpendicularly outside the plane of the figure)