How Is Coulomb’s Law Different to Newton’s?

Introduction:

Coulomb’s law and Newton’s law of universal gravitation are both fundamental principles in physics that describe the forces between objects. While Newton’s law explains the gravitational force between two masses, Coulomb’s law deals with the electrical force between two charged objects. In this article, we will explore the differences between Coulomb’s law and Newton’s law and shed light on their applications and implications in the world of physics.

Coulomb’s Law:

Coulomb’s law, formulated by French physicist Charles-Augustin de Coulomb in the late 18th century, states that the force between two charged objects is directly proportional to the product of their charges and inversely proportional to the square of the distance between them. Mathematically, it can be expressed as:

F = k * (q1 * q2) / r^2

Where F represents the force between the two charges, q1 and q2 denote the magnitudes of the two charges, r is the distance between them, and k is the electrostatic constant.

Newton’s Law of Universal Gravitation:

Newton’s law of universal gravitation, established by Sir Isaac Newton in the 17th century, describes the force of gravitational attraction between two masses. It states that the force between two masses is directly proportional to the product of their masses and inversely proportional to the square of the distance between them. The equation is given by:

F = G * (m1 * m2) / r^2

Where F represents the gravitational force, m1 and m2 represent the masses of the two objects, r is the distance between them, and G is the gravitational constant.

Differences between Coulomb’s Law and Newton’s Law:

1. Nature of the Forces:

Coulomb’s law deals with electrical forces between charged objects, while Newton’s law explains gravitational forces between objects with mass. Electrical forces can be either attractive or repulsive, depending on the charges involved, while gravitational forces are always attractive.

2. Magnitude of the Forces:

The electrostatic force described by Coulomb’s law is much stronger than the gravitational force described by Newton’s law. This is due to the fact that the electrostatic constant (k) is significantly larger than the gravitational constant (G).

3. Range of the Forces:

Gravitational forces have an infinite range, meaning they act on objects regardless of the distance between them. On the other hand, electrical forces have a finite range and decrease rapidly with distance. This is because electromagnetic interactions are mediated by photons, which have limited reach.

4. Significance in Everyday Life:

Coulomb’s law has a more noticeable impact on our daily lives compared to Newton’s law of gravitation. Electrical forces govern the behavior of charged particles, leading to the functioning of electronic devices, power generation, and even the interactions within our bodies, such as nerve impulses and muscle contractions.

FAQs:

Q: Can Coulomb’s law be applied to objects with mass?

A: No, Coulomb’s law only applies to objects with electric charge. If the objects have mass but no charge, Newton’s law of universal gravitation should be used instead.

Q: What happens when both electrical and gravitational forces are present?

A: In scenarios where both electrical and gravitational forces are significant, the forces add up as vectors. This means that the total force experienced by an object will be the vector sum of the individual electrical and gravitational forces acting on it.

Q: Are Coulomb’s law and Newton’s law limited to point charges and point masses, respectively?

A: Both laws can be used to describe the forces between extended objects as long as the distances involved are much larger than their sizes. For more accurate calculations involving complex geometries, more advanced mathematical models and techniques are required.

Conclusion:

Coulomb’s law and Newton’s law of universal gravitation are two fundamental principles in physics that describe the forces between objects. While Coulomb’s law focuses on the electrical forces between charged objects, Newton’s law explains the gravitational forces between objects with mass. Understanding the differences between these laws is crucial for comprehending the behavior of charged particles and the mechanics of celestial bodies in the universe.