13. What drives planetary motion in space?
A). The Sun
B). Mass of Planets
C). Inertia
D). Gravity
D). Gravity
The correct answer is D). Gravity.
Gravity is the force that drives planetary motion in space. It is the mutual attraction between all objects with mass in the universe, including planets. Gravity exerts a pulling force on each planet, keeping them in orbit around the Sun or around other celestial bodies. The gravitational force between a planet and the Sun is what holds the planet in its elliptical orbit.
The correct answer is D) Gravity.
Gravity is the force that drives planetary motion in space. It is a fundamental force of nature that causes objects with mass to be attracted to each other. In the case of planetary motion, the gravitational force exerted by the Sun plays a significant role.
To understand this, let's take a closer look at how gravity affects planets. Imagine a planet orbiting the Sun. The gravitational force between the planet and the Sun pulls them towards each other. However, the planet is also moving forward due to its inertia, which is another property of objects in motion to continue moving in a straight line unless acted upon by a force.
The combination of the gravitational pull from the Sun and the forward motion of the planet creates a balanced force known as centripetal force. This force acts perpendicular to the planet's direction of motion and keeps the planet in a curved orbit around the Sun. Without gravity, the planet would move off in a straight line instead of following its orbit.
Therefore, gravity is the force that drives and maintains the planetary motion in space.