Gravitation Reasonings

An apple falls due to attraction of earth. Does the apple also attract the earth?

Yes, the apple also attracts the earth. But the acceleration of the earth due to this attractive force is negligible because of very small size of the apple i.e.

\[g=\frac{Gm}{R^2}\] where, $m$ and $R$ are the mass and radius of the apple respectively.

The value of gravitational constant $(G)$ is very small i.e. $6.67×10^{-11}$ $\text{Nm}^2/\text{kg}^2$. Since the mass of the apple is also very small, the acceleration $g$ is negligible.

But in the case of earth, it is so massive that $g$ becomes $9.8$ $\text{m/s}^2$ which can be felt by everyone.