At a certain location in Africa, a compass points 12° west of the geographic north. The north tip of the magnetic needle of a dip circle placed in the plane of magnetic meridian points 60° above the horizontal. The horizontal component of the earth’s field is measured to be 0.16 G. Specify the direction and magnitude of the earth’s field at the location.
Given that, Angle of declination, θ=12∘ Angle of dip, δ=60∘ Horizontal component of earths magnetic field, BH = 0.16 G We can write, BH=Bcosδ where, B is Earths magnetic field at the given location B=cosδBH B=cos60∘0.16 B=0.32G=0.32×10−4T Earths magnetic field lies in the vertical plane, 12∘ West of the geographic meridian, making an angle of 60∘ (upward) with the horizontal direction. Its magnitude is 0.32×10−4T.
