Answer:
Gravitational force exists between any two bodies having mass. It is proportional to the mass of two bodies and inversely proportional to the square of distance between them.

Thus, with increase in distance, the gravitational force decreases.
Acorn falls to Earth because of the following two reasons:
1. Mass of Earth > Mass of Moon
2. Acorn is closer to the Earth
Thus, the gravitation force of attraction is greater towards the Earth.