**Newtons Universal Law of Gravitation**

The principle that two bodies exert a gravitational attraction for each other that increases as their masses increase and as the distance between them decreases. In mathematical terms, the force equals the product of the two masses multiplied by the gravitational constant and divided by the square of the distance. Also called law of gravitation, law of universal gravitation.To know more about Newtons Universal Law of Gravitation,watch Newtons Universal Law of Gravitation Video to learn more .

**Idea:** **Newton’s Universal Law of Gravitation**

States that any two objects exert a gravitational force of attraction on each other. The direction of the force is along the line joing the objects The magnitude of the force is proportional to the product of the gravitational masses of the objects, and inversely proportional to the square of the distance between them.

The **inertial mass** of an object determines the amount of force needed to produce a given acceleration of that object. The **gravitational mass** determines the force of gravitational attraction between two bodies. In Newtonian mechanics, these two masses have no obvious connection with each other. Nonetheless, it was observed empirically that they are numerically equal. This remarkable fact was known for centuries, but remained unexplained until Einstein’s General Theory of relativity.

Newton’s gravitational constant is *extremely small* when expressed in terms of laboratory sized objects: the gravitational force between two 1 *kg* objects separated by 1 *m* is only 6.67 x 10^{– 11} Newtons.

**Gravitional Potential Energy:**

Due to the gravitational force of attraction, any two objects with masses *m*_{1} and *m*_{2} located a distance *r* apart have the ability to do work. Hence they have potential energy. The **gravitational potential energy** of such objects is:

- Recall that only differences in potential energy are physically relevant. In the above, the zero of gravitational potential energy has been arbitrarily chosen to be zero at
*r*= . i.e. when the objects are infinitely far apart.

Useful for CBSE, ICSE, NCERT & International Students

Grade :9

Subject : Physics

Lesson : Gravitation

Topic:Newtons Universal Law of Gravitation Video

Visit www.oztern.com to find personalized test preparation solutions for Pre Medical – AIPMT, AIIMS, JIPMER, State, Pre Engineering – IIT JEE, JEE MAIN, BITSAT, State and Foundations – Class 6 to 10