Question

in regards to Earth's wobble and precession

i) which type of event causes a change in the position of the equator on the earth?

ii)which type of event is cause by rearrangement of mass within the Earth?

iii)which type of event is caused by torques from the Sun and Moon?

Answer 1

i) Earth's equator is at 23.5 degree w.r.t. earth's orbit. Due to bulge at the equator and varying gravitational pull of the sun, eath's obliquity changes as 22.1 to 24.5 to 22.1 over the period of 26000 years, which is called precession.
And due to monn's gravity Earth's equator wobble due the precession, which is called Nutation also. Period of nutation ids 13.6 yrs.

ii) Tactonic plate movement and Tide are the main causes due to which rearrangement of mass happens.

iii) Precession and Nutation are effect of Sun and Moon's torque on equatorial bulge of the Earth.