In accordance with the Bohr’s model, find the quantum number that characterises the earth’s revolution around the sun in an orbit of radius 1.5 × 1011 m with orbital speed 3 × 104 m/s. (Mass of earth = 6.0 × 1024 kg.)

Angular momentum is given by the relation:


Where M is the mass of Earth and is equal to 6.0 × 1024 kg.


v is the orbital speed of Earth = 3 × 104 m/s.


r is the orbital radius of Earth= 1.5 × 1011 m


n is the quantum number



substituting the values, we get



on calculating, we get


n =2.6 × 1074


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