# Electrostatic equilibrium problem

• ChiralSuperfields
In summary, the conversation is about someone asking for help with understanding a problem involving an electric field outside of a sphere. The expert explains that the electric field of a sphere is equivalent to that of a point charge and provides a formula for calculating it. The person then asks why the situation is impossible, and the expert points out that the calculated value does not match the value on the graph.

#### ChiralSuperfields

Homework Statement
Relevant Equations
For this problem,

Many thanks!

anuttarasammyak
What would be the magnitude of the electric field just outside the sphere?

ChiralSuperfields
kuruman said:
What would be the magnitude of the electric field just outside the sphere?
Thank you for your reply @kuruman ! The electric field of a sphere is equivalent to that of a point charge so ## E = \frac {40 \times 10^{-9}k_e}{0.15^2} ##

Many thanks!

So why is the situation impossible?

ChiralSuperfields
kuruman said:
So why is the situation impossible?
Thanks for your reply @kuruman ! Thinking... Its got to me something to do with the electric field.

Callumnc1 said:
Thanks for your reply @kuruman ! Thinking... Its got to me something to do with the electric field.
Yes. Look at the plot and then look at your post #3.

ChiralSuperfields
kuruman said:
Yes. Look at the plot and then look at your post #3.
Oh thanks @kuruman ! The calculated value for the electric field at the surface of the charge is not equal to that value on the graph.

## 1. What is electrostatic equilibrium?

Electrostatic equilibrium is a state in which the electric charges within a system are evenly distributed and there is no net flow of electric current. This means that the electric field and potential within the system are constant and there is no movement of charges.

## 2. How is electrostatic equilibrium achieved?

Electrostatic equilibrium can be achieved by placing conductors in close proximity to each other, as the charges on the conductors will repel each other until they reach a state of equilibrium. It can also be achieved by grounding a conductor, which allows excess charges to flow away and reach equilibrium.

## 3. What is the importance of electrostatic equilibrium?

Electrostatic equilibrium is important in many practical applications, such as in electronic devices, power transmission, and lightning protection. It also plays a crucial role in understanding the behavior of atoms and molecules, as well as the formation of lightning and other natural phenomena.

## 4. What are some factors that can disrupt electrostatic equilibrium?

Factors that can disrupt electrostatic equilibrium include the presence of external electric fields, changes in temperature, and the movement of charged particles within the system. Conductors that are not properly insulated can also disrupt electrostatic equilibrium.

## 5. How is electrostatic equilibrium related to Coulomb's law?

Coulomb's law states that the force between two charged particles is directly proportional to the product of their charges and inversely proportional to the square of the distance between them. In electrostatic equilibrium, the forces between charges are balanced, which means that the net force on each charge is zero. This is in accordance with Coulomb's law and helps to maintain the state of equilibrium.