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How is velocity calculated at perihelion?

Answer 1

4-significant digits (sd) approximation: 30.79 km/s

Simple calculation of velocity at aphelion and perihelion:

If V is the speed at the distance equal to semi-major axis a ( at an end of the minor axis) of the orbit, Vp and Va are speeds at perihelion and aphelion and e is the orbit eccentricity. #Vp = V((1+e)/(1-e)) and Va = V((1-e)/(1+e))# V - 29.774 km/s, nearly. e = 0.01671, nearly.

Perpendicular to the radius separating the Sun from the Earth are the directions of motion at perihelion and aphelion.

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Answer 2

Luca de

At perihelion, the planet is at its closest point to the sun, so its velocity is at its maximum. Therefore, the velocity at perihelion can be calculated using the equation for the area of an ellipse: [ v_{\text{peri}} ] Where ( v_{\text{peri}} ) is the velocity at perihelion, ( G ) is the gravitational constant, ( M ) is the mass of the sun, and ( m ) is the mass of the planet.

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.