Question

1. how would the motion of a planet change if it were to stop moving relative to the sun, and what analogy is used to explain this? 3. how would the motion of the planets change without the sun? 4. what shape do the orbits of most modern - day planets take, and how does this differ from a perfect circle? 5. according to keplers first law, where is the sun located in relation to the orbit of a planet?

Explanation:

1. A planet moving relative to the Sun has orbital - motion. If it stops, it would fall towards the Sun due to gravitational pull. The analogy of a ball on a string being swung (where the string tension is like the Sun's gravity and the ball's motion is like the planet's orbital motion) can be used. If the ball - swinger stops moving the ball, it falls towards the center.
2. Without the Sun, the gravitational force that keeps planets in orbit around it would disappear. Planets would move in a straight - line path tangent to their previous orbits, according to Newton's first law of motion.
3. Most modern - day planets have elliptical orbits. An ellipse is different from a perfect circle in that it has two foci (a circle has one center), and the distance from a planet to the Sun varies as it moves along the ellipse (while in a circle, the distance from the center to any point on the circle is constant).
4. According to Kepler's first law, the Sun is located at one of the two foci of a planet's elliptical orbit.

Answer:

1. The planet would fall towards the Sun due to gravity. Analogy: A ball on a string that stops being swung falls towards the center.
2. Planets would move in a straight - line path tangent to their previous orbits.
3. Most planets have elliptical orbits. An ellipse has two foci and variable distance to the Sun, while a circle has one center and constant radius.
4. The Sun is located at one of the two foci of a planet's elliptical orbit.