Keeping the radius of the earth unchanged if the mass of the earth is doubled , then what will be the length of a day?

Keeping the radius of the earth unchanged if the mass of the earth is

1.	Keeping the radius of the earth unchanged if the mass of the earth is doubled , then what will be the length of a day?
Answer» Solution : If the present angular velocity is `omega` and the changed angular velocity is `omega`, then according to the principle of conservation of angular momentum, `Iomega= I.omega`. [ here `I` and `I.` are the present and thechanged MOMENTS of INERTIA of the earth respectively ] `:. " " (2)/(5) MR^(2)xx(2pi)/(24)=(2)/(5) xx2M xxR^(2)xx(2pi)/(T.)` [ here the present mass of the earth is M, its RADIUS is R and the changed length of a day is T. ] or, `(1)/(24)=(2)/(T.)or,T.`=48 hours So, the length of a day will be 48 h.