The electrostatic force is the force of attraction or repulsion between two charged particles. It is also called Coulomb’s force or Coulomb’s interaction. For example, the force between the protons and electrons in an atom is electrostatic and is responsible for the atom’s stability. In chemistry, the electrostatic bonding force is important and binds an ionic molecule.

Question

The laws of electrostatics were discovered by French physicist Charles Augustin de Coulomb in 1785 and are known as Coulomb’s law.

Laws Governing Electrostatic Force
Coulomb’s Law
The electrostatic force between two charged particles can be quantified by Coulomb’s law. It is usually applied to point charges and gives a relationship between the electrostatic force, the magnitude of the charges, and separation distance. According to this law, the force between the two particles is,

Directly proportional to the product of the magnitude of the charges
Inversely proportional to the square of the distance between the two charges
Suppose the two charged particles are brought close to one another. There will be an attraction if the charges are opposite, or if one is positive and the other negative. On the contrary, the charges will repel if both of them are positive or negative. In other words, like charges repel and unlike charges attract.

Electrostatic Force Equation
Let us assume that q1 and q2 are the amounts of charges on the two particles separated by a distance r. According to Coulomb’s law, the electrostatic force between the two charges is given by the following equation.

Units = N (Newtons)

Here, k is called Coulomb’s constant. Its value is 9 x 109 N.m2.C-2. Generally, q1 and q2 can be positive or negative. When two opposite point charges are placed close to each other, the force is attractive and hence, its sign is negative.

Properties of Electrostatic Force
Here are some facts and characteristics of the electrostatic force.

Like charges repel, and opposite charges attract
Directly proportional to the product of the magnitude of the charges
Inversely proportional to the distance of separation between the charges
Question 1
Like charges attract, and opposite charges repel.

True
False
Question 2
Match the particle with its correct charge

Column A
1.
Proton:
Proton
2.
Electron:
Electron
3.
Neutron:
Neutron
Column B
a.Negative
b.Neutral
c.Positive
Question 3
As the distance between two charges is decreased, or as they become closer together, the electrostatic force between the two charges will _______.

a
not change
b
increase
c
become more magnetic
d
decrease
Question 4
As the magnitude (the size) of the two charges in close contact increases, what happens to the size of the electrostatic force between them?

a
there is no way to determine how the force will be affected
b
the force increases
c
the force decreases
d
there is no change in the force

Answer 1

Here are the answers to the questions based on the information provided:

Question 1:
Like charges attract, and opposite charges repel.
Answer: False (It is actually the opposite: like charges repel, and opposite charges attract.)

Question 2:
Match the particle with its correct charge
Column A | Column B
--- | ---

1. Proton: | c. Positive
2. Electron: | a. Negative
3. Neutron: | b. Neutral

Question 3:
As the distance between two charges is decreased, or as they become closer together, the electrostatic force between the two charges will _______.
Answer: b. increase

Question 4:
As the magnitude (size) of the two charges in close contact increases, what happens to the size of the electrostatic force between them?
Answer: b. the force increases

If you have any further questions or need more clarification, feel free to ask!