The earth rotates about the sun in an elliptical orbit. At which point will its velocity be maximum?

Assertion: A body weighs $X$ newton on the surface of the earth. Its weight at a height equal to half the radius of the earth will be $\frac{2X}{5}$.

Reason: $g^{\text{'}}=g\frac{R^2}{{\left(R+h\right)}^2}$.

The gravitational force between two spheres of masses $m$ and $M$ situated in the air is $F$. Now the space around the masses is filled with a liquid of specific gravity $3$. What will be the gravitational force now?

Assertion: The artificial satellite does not have any fuel but even then it remains orbiting around the earth.

Reason: The necessary centripetal force required to move the satellite in an orbit around the earth is provided by the gravitational force of attraction between the satellite and the earth.