Newton law of graviton and formula

• The Universal Law of gravitation was coined by Sir <a href="https://www.toppr.com/bytes/isaac-newton/" target="_top">Issac Newton</a>.
• As per the law:

Everybody in the universe attracts every other body with a force, which is directly proportional to the product of their masses and inversely proportional to the square of distance between them. The force acts along the line joining the two bodies

• This law is fundamental to understanding gravitation for class 9. For understanding this concept better, let us consider two objects of masses M and m that are at a distance r from each other as shown in the figure below:

• Now, let’s assume that F is the force of attraction between two objects P and Q.
• So, if we take the universal law of gravitation into account, then the force F is proportional to the product of masses of objects P and Q that is
  F∝M×m (1)
  and the force is inversely proportional to the square of distance between these two objects that is
  F∝1/r^2 (2)
• When we combine both <a href="https://www.toppr.com/bytes/arrhenius-equation/" target="_top">equation</a>s (1) and (2), we derive
  F∝Mm/r^2 (3)
  or
  F=GMm/r^2 (4)
• Note that in this case, G is the constant known as Universal Gravitational constant.
• Nm2Kg−2 is the SI unit of gravitational constant G
• The value of G was first established by Henry Cavendish (1731-1810) and it is
  G=6.673×10−11Nm2Kg−2