If a magnet is suspended at an angle of #30^o# to the earth magnetic meridian , the dip needle makes angle of #45^o# with the horizontal . the real dip is ?

1 Answer
Apr 16, 2017

Answer:

Real dip #theta=40.9^@#

Explanation:

Let the vertical component of earth's magnetic field be V and its horizontal component at magnetic meridian be H.

Then the angle of dip #theta# at magnetic meridian will be given by

#tantheta=V/H......[1]#

When the dip needle is suspended at an angle of #30^@# to the earth magnetic meridian then it makes an angle #45^@# with the horizontal.

In this situation vertical component of earth's field responsible for its orientation with the horizontal direction, remains same as #V# but the component in horizontal direction becomes #Hcos30^@#

So #tan45^@=V/(Hcos30^@)#

#=>V/H=cos30^@.......[2]#

Comparing [1] and [2] we get

#tantheta=cos30^@=sqrt3/2#

#=>theta=tan^-1(sqrt3/2)~~40.9^@ #