Question

the planet neptune orbits the sun. neptune is much less massive than the sun.
models of neptuness orbit are shown below. each model shows neptune as a dot, at one position along its orbit.
which model correctly shows the gravitational forces that neptune and the sun exert on each other?
the sizes of neptune and the sun are not shown to scale.
choose 1 answer:
a
b
c
d

Explanation:

To determine the correct model, we use Newton's third law of motion, which states that the gravitational force exerted by Neptune on the Sun is equal in magnitude and opposite in direction to the gravitational force exerted by the Sun on Neptune. This means the force vectors should be along the line connecting Neptune and the Sun, pointing toward each other (since gravity is an attractive force).

• Option A: The forces are not toward each other (Sun's force direction is incorrect relative to Neptune's).
• Option B: The force vectors are not along the line connecting them and not toward each other.
• Option C: The force on the Sun (from Neptune) and the force on Neptune (from the Sun) are along the line connecting them, equal in magnitude (vector lengths, though size not to scale, direction is toward each other), and opposite in direction.
• Option D: The force vectors are not along the line connecting them and not toward each other.

So, Option C follows Newton's third law for gravitational interaction.

Answer:

C. The model where the gravitational force on the Sun (from Neptune) and the gravitational force on Neptune (from the Sun) are along the line connecting them, pointing toward each other.