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Grade 1010 grade science

  1. Let the period of revolution of a planet at a distance R from a star be T . prove that if it was at a distance of 2R from the star its period of revolution will be √8 T.

Profile image of Vijay mohite
8 Years agoGrade 10
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1 Answer

Profile image of Eshan
8 Years ago
Dear student,

From Kepler’s law of planetary motion,

T^2\propto R^3
Hence(\dfrac{T_2}{T_1})^2=(\dfrac{2R}{R})^3
\implies \dfrac{T_2}{T}=2^{3/2}=\sqrt{8}
\implies T_2=\sqrt{8}T