The motion of planets in the solar system is an example of the conservation of:

The Earth revolves around the Sun in one year. If the distance between them becomes double,the new period of revolution will be

The period of a planet around the sun is $8$ times that of earth. The ratio of the radius of the planet's orbit to the radius of the earth's orbit is:

The time period of a satellite in a circular orbit of radius $R$ is $T$. The period of another satellite in a circular orbit of radius $9R$ is............ $T$.

The Earth revolves around the Sun in an elliptical orbit with a mean radius of $9.3 \times 10^{10} \ m$ in a period of $1$ year. Assuming that there are no outside influences,which of the following statements is true?

Kepler discovered