Gravitation

What is Gravitation?

Gravitation is the force of attraction that exists between all objects with mass. It’s the force that makes things fall to the ground and keeps the planets in orbit around the Sun. Sir Isaac Newton first described this force in the 17th century and formulated the law of universal gravitation.

The Law of Universal Gravitation:

Newton’s law of universal gravitation states that every object in the universe attracts every other object with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centers. 

  • This law can be expressed by the formula:

where:

  • F is the gravitational force between the masses,
  • G is the gravitational constant (6.67×10-11Nm2/kg2 )
  • m1​ and m2​ are the masses of the objects,
  • r is the distance between the centers of the masses.

Key Notes:

  • Mass: The amount of matter in an object. The greater the mass, the stronger the gravitational force it exerts.
  • Distance: Gravitational force weakens with distance. As objects move farther apart, the force of gravity between them decreases rapidly.
  • Weight: Weight is the force with which an object is attracted towards the center of the Earth (or any other celestial body). It is directly proportional to the mass of the object but depends on the local gravitational field strength.

Acceleration Due to Gravity:

On Earth, all objects experience a gravitational acceleration towards its center. This acceleration is denoted by g and is approximately 9.8 m/s2

F= mâ‹…g

where:

  • F is the weight of the object,
  • m is its mass,
  • g is the acceleration due to gravity.

Conclusion: Gravitation is a fundamental force that governs the motion of celestial bodies, the falling of objects, and many other phenomena. Understanding how gravity works helps us explain a wide range of natural occurrences and is crucial to our understanding of the universe.

Let’s Practice!