Question

The following table shows the distance from the sun of some unknown planets of equal mass.

Distance from Sun
Planet Distance from Sun
Y 1 AU
Z 0.39 AU


Which of the following best explains which planet revolves at a slower speed?
Planet Y, because the sun pulls it with a greater force
Planet Z, because the sun pulls it with a greater force
Planet Y, because the gravitational force is weakened by distance
Planet Z, because the gravitational force is strengthened by distance

Answer 1

The answer to your question is C: Planet Y, because the Gravitational force is weakened by the distance. Hope this helps!

Answer 2

Option (3)

Step-by-step explanation:

Given that, planet Y is at a distance of 1 AU away from the sun, and the planet Z is at a distance 0.39 AU away from the sun.

From Kepler's law of astronomical unit, it is known that the planets that are closer to the sun move at a faster rate in comparison to the distant planets because of their high gravitational force.

So from the given condition, it can be concluded that the planet Y is at a greater distance (1 AU) from the sun, which will orbit the sun at a much slower rate because of its comparatively weaker gravitational force, as the speed of a planet is directly affected by the distance from the sun.

Thus, the correct answer is option (3).