Question

Let the magnetic field on earth be modelled by that of a point magnetic dipole at the centre of earth. The angle of dip at a point on the geographical equator

.

• A. is always zero
  
  
• B. can be positive or negative
  
  
• C. is bounded
• D. can be zero at specific points
  
  

Answer 1

Answer: (B), (C), (D)

can be zero at specific points

The angle of dip is the angle made with the horizontal by the Earth's magnetic field lines. It is the angle formed between the magnetic axis and the geographical axis of the earth. The angle can be positive as well as negative. Now the magnetic dip is only zero (nearly zero) at the equator because the magnetic lines of force are parallel to the surface (i.e. horizontal). Thus, the value ranges from $-{90}^{\circ }\text{to}+{90}^{\circ }$.

Final Answer: (b), (c), (d)