Universal Law of Gravitation

The Universal Law of Gravitation is one of the most important laws in physics. It was proposed by Sir Isaac Newton in the 17th century. This law helps us understand how objects attract each other in the universe. It explains why an apple falls from a tree and why planets orbit the sun. The gravitational force is the force of attraction between any two objects that have mass.

What is the Universal Law of Gravitation?

The Universal Law of 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 them.”

This means:

• If the mass of either object increases, the gravitational force increases.
• If the distance between them increases, the force decreases.

This is known as the inverse square law of gravitation.

Law of Gravitation Formula

The formula for universal law of gravitation is:

F=G⋅m1⋅m2r2F = \frac{G \cdot m_1 \cdot m_2}{r^2}F=r2G⋅m1⋅m2

Where:

• F = Gravitational force
• G = Gravitational constant (6.674 × 10⁻¹¹ N·m²/kg²)
• m₁ and m₂ = Masses of the two objects
• r = Distance between the centers of the two objects

This formula helps calculate the force between two objects based on their mass and distance relationship.

Real-Life Examples

Here are some real-life examples of universal gravitation:

• Earth’s gravitational pull keeps us grounded.
• The moon orbits the Earth due to gravity.
• Objects fall when dropped because of Newton’s gravitational theory.
• The sun holds planets in their orbits using gravitational force.

These are all applications of gravitational law in everyday life.

Relationship Between Mass and Distance

• The greater the mass of the objects, the stronger the gravitational attraction.
• The farther the objects are from each other, the weaker the force.

This is why the attraction between masses like the Earth and the moon is noticeable, but the gravitational pull between small objects around us is very weak.

Newton’s Contribution to Physics

Isaac Newton’s contribution to physics is huge. Along with the universal law of gravitation, he also gave the three laws of motion. These laws, together with his gravity theory, helped scientists understand how things move and interact in space and on Earth.

Importance of Universal Law of Gravitation in Physics

• It explains the physics of falling objects.
• It helps predict the motion of planets and satellites.
• It plays a key role in space travel and astronomy.
• It is used in studying orbiting due to gravity.

Simple Derivation (Step-by-Step)

While the full mathematical derivation of universal law of gravitation involves advanced concepts, a basic idea can be shown using Newton's observations:

• Objects attract due to mass.
• More mass = more force.
• More distance = less force.
• Combine these into a formula → leads to the gravity equation.

Summary Table

Conclusion

The Universal Law of Gravitation is a simple yet powerful law that explains how the force of gravity works in the universe. Whether it's the Earth’s gravitational pull or the orbit of planets, this law helps us understand it all. Thanks to Sir Isaac Newton, we have a clear explanation of how everything in space is connected by gravity.