Question

The external force for the earth-moon system is due to the?

Answer 1

Explanation

1. The gravitational force acts internally on the earth and moon. According to Newton's law of gravitation, there is a force acting between any two objects that is directly proportional to the product of their masses and inversely proportional to their distance from one another.
   It is represented as $\mathrm{F}=\mathrm{G}\frac{{\mathrm{m}}_1{\mathrm{m}}_2}{{\mathrm{r}}^2}$, here, $\mathrm{G}$ is the gravitational constant.
2. Scalar gravity is a measure of gravity. Its value is constant throughout the cosmos and unaffected by the type, size, and composition of the medium separating the bodies. The value of G in SI unit is $6.67\times {10}^{-11}{\mathrm{Nm}}^2/{\mathrm{kg}}^2$.

Supporting data for Newton's law of gravitation:

1. This law serves as the foundation for the explanation of the rotation of the earth around the sun or the moon around the earth.
2. Based on this law, predictions concerning solar and lunar eclipses were consistently accurate.
3. The force of attraction between the moon and ocean water causes tides to form in the ocean.
4. On the basis of this law, predictions concerning the orbits and lifetimes of contemporary artificial satellites are shown to be extremely accurate.

Important aspects of Gravitational force:

According to Newton’s law of gravitation, the gravitational force of attraction between two given objects,

1. Is independent of the nature of the intermediary medium.
2. Is independent of the presence or absence of other objects.
3. So, the external force acting on both the earth and moon is the sun's attraction, but the gravitational attraction of the earth and moon is caused by gravity.

Hence, the external force for the moon-earth system is due to the sun's attraction.