Q48 of 149 Page 195

Calculate the ratio of the angular momentum of the earth about its axis due to its spinning motion to that about the sun due to its orbital motion. Radius of the earth = 6400 km and radius of the orbit of the earth about the sun = 1.5 x 108 km.

The ratio of the angular momentum of the earth about its axis due to its spinning motion to that about the sun due to its orbital motion is


Given


The radius of the earth is and radius of the orbit of earths revolution is given as


Formula used


The formula for the angular momentum is the product of the moment of inertia with the angular velocity of the planet that is revolving around or the orbit



where


L is the angular momentum, I is the moment of Inertia, is the angular velocity.


Explanation


The angular momentum of earth is



And the value of moment of inertia of earth is



Now the value of the sun’s average mass is



Calculating ratio of the mass of sun and the mass of earth we get the value





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