Newtons law of gravitation¶
Every particle of matter in the universe affects every other particle with a force that is directly proportional to the product of the masses of the particles and inversely proportional to the square of the distance between them.
\[
F_g = G \frac{m_1m2}{r^2}
\]
\(m_1\) is the mass of the first object
\(m_2\) is the mass of the second object
\(G=6.674 \times 10^{-11}\) is the gravitational constant
The gravitational force between familiar objects (car, dog) is small, it grows as objects get heavier.