At a given place on the earths surface, the horizontal component of magnetic field is 3.2×10−5T and the resultant magnetic field is 6.4×10−5T. The angle of dip at that place is:
BH=3.2×10−5 T
B=6.4×10−5 T
BcosΘ=BH
cosΘ=BHB
=3.2×10−56.4×10−5
=12
Θ=60∘