The magnetic field of the earth can be modelled by that of a point dipole placed at the centre of the earth. The dipole axis makes an angle of 11.3° with the axis of the earth. At Mumbai, declination is nearly zero. Then,
A. the declination varies between 11.3° W to 11.3° E
B. the least declination is 0°
C. the plane defined by dipole axis and the earth axis passes through Greenwich
D. declination averaged over the earth must be always negative
Answer:A
The magnetic field of the earth can be modelled by that of a point dipole placed at the centre of the earth. The dipole axis makes an angle of 11.3° with the axis of the earth. At Mumbai, declination is nearly zero. Then,
A. the declination varies between 11.3° W to 11.3° E B. the least declination is 0° C. the plane defined by dipole axis and the earth axis passes through Greenwich D. declination averaged over the earth must be always negative