Geometric radius of the Earth is ___________ in the equatorial region .

Geometric radius of the Earth is ___________ in the polar region .

Nights and days in equatorial region are -

The radius of the earth is 6400 km. What will be the value of the centrifugal acceleration at the equatorial region due to the earth's diurnal motion?

For what value of the angular velocity of the earth, the acceleration due to gravity in the equatorial region would have been zero ? The average density of the earth's material =5.5 g*cm^(-3) and G=6.67xx10^(-8) CGS unit. Find the ratio of this calculated value and the present value of the angular velocity of the earth.