A earth's magnetic field at geomagnetic poles has a magnitude `6.2 xx 10^(-5) T`. Find the magnitude and the direction of the field at a point on the earth's surface where the radius makes an angle of `135^@` with the axis of the earth's assumed magnetic dipole. What is the inclination (dip) at this point?

Explanation

4.9 xx 10^(-5) T`.
The angle `alpha` of this field with the vertical is given by
`tanalpha = (tantheta)/2 = (tan 135^@)/2 = -0.5`
giving `alpha = 153^@`.
This sinclination (dip) is the angle made by the earth's magnetic field with the horizontal plane. Here it is `153^@ - 90^@ = 63^@` below the horizontal.