Many of the planets in the solar system have orbits of similar shapes, but they orbit at very different speeds. Why do the planets orbit at different speeds?
A.
Planets are kept in their orbits by tension force, which is affected by the atmospheric pressure of a planet.
B.
Planets are kept in their orbits by electromagnetic force, which is affected by the diameter of a planet.
C.
Planets are kept in their orbits by friction, which is affected by the temperature of a planet.
D.
Planets are kept in their orbits by gravity, which is affected by the mass of a planet.
D.
Planets are kept in their orbits by gravity, which is affected by the mass of a planet.
The correct answer is D. Planets are kept in their orbits by gravity, which is affected by the mass of a planet. The greater the mass of a planet, the stronger its gravitational pull. As a result, planets with larger masses experience a stronger gravitational force, which causes them to orbit at faster speeds. Conversely, planets with smaller masses experience a weaker gravitational force, making their orbital speeds slower.
The correct answer is D. Planets are kept in their orbits by gravity, which is affected by the mass of a planet.
To understand why planets orbit at different speeds, we need to consider the relationship between gravity, mass, and orbit. The force of gravity between two objects depends on their masses and the distance between them. In the case of planets orbiting the sun, the sun's gravitational force acts as the centripetal force, keeping the planets in their orbits.
According to Newton's law of universal gravitation, the force of gravity between two objects is directly proportional to the product of their masses and inversely proportional to the square of the distance between them. This means that the more massive an object, the stronger its gravitational pull.
When planets are closer to the sun, the gravitational force is stronger, causing them to accelerate and move faster in their orbits. Similarly, when planets are farther from the sun, the gravitational force is weaker, resulting in slower speeds.
Therefore, the differing speeds of planets in their orbits are primarily due to variations in their masses and their distances from the sun. Planets with larger masses and closer distances to the sun will have faster orbital speeds, while those with smaller masses and farther distances will have slower speeds.