Non-Circular Orbits Flashcards

All 6 cards in this deck

What shape are the orbits of the planets around the Sun?

Slightly elliptical (almost circular), with the Sun at one focus.

What shape is the orbit of a comet?

A very elongated (highly elliptical) orbit around the Sun.

Where in its orbit does a comet move fastest?

When it is closest to the Sun, where the gravitational force on it is greatest.

For a stable orbit, what must happen to the orbital radius if the orbital speed increases?

e.g. a satellite is speeded up

The radius must decrease.

The satellite moves into a lower, faster orbit.

True or false? A satellite in a low orbit travels more slowly than one in a high orbit.

False. The smaller the orbital radius, the faster the satellite must travel for a stable orbit.

What shape are the orbits of moons (natural satellites) around their planets?

Almost circular (slightly elliptical) orbits around the planet.