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Question
Out of aphelion and perihelion, where is the speed of the earth more and why?
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Solution
Aphelion is the location of the earth where it is at the greatest distance from the sun and perihelion is the location of the earth where it is at the nearest distance from the sun. According to the diagram given below point A represents aphelion and point P perihelion.
According to Kepler's second law, a real velocity is constant. So, `r_p xx v_p = r_A xx v_A`
⇒ `r_A/r_p = v_p/v_A`
Therefore, `r_A > r_p`. So `v_p > v_A`
Therefore, the speed of the earth is more at the perihelion than at the aphelion.
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