A comet moves in an elliptical orbit around the Sun

PHYSICS · Single correct · A Level · Physics · Fields and their consequences · Fields and their consequences

Problem

A comet moves in an elliptical orbit around the Sun. At aphelion A, its distance from the Sun is

1.5\times10^{11}\,\text{m}

and its speed is

30\,\text{km s}^{-1}

. What is its speed (to the nearest km s

^{-1}

) when it reaches point B where the distance from the Sun is

1.0\times10^{11}\,\text{m}

? (a) 42 km s

^{-1}

(b) 45 km s

^{-1}

^{-1}

(d) 67 km s

^{-1}