Why Does a Static Electric Discharge Make a Sound and Light?

[Crystal037]

Homework Statement

Why do electric discharge due to the accumulation of electric charge produces a sparkle or a crackle which we can hear

Relevant Equations

Does electric discharge release energy

Since electrical charges causes a sparkle or a crackle which is light and sound.
Also light and sound are forms of energy
does that mean that electrical discharge releases energy and if yes then the release of energy have an effect on charge

 

[RPinPA]

Yes, energy is released. I don't know what you mean by an effect on charge, but there is charge flowing, to equalize a charge difference.

An electrical spark is a small version of a lightning strike.

 

[Crystal037]

How does that energy come from. Due to potential energy or what?
And by the effect of energy release on charge i mean if the chrge is decresed or increased due to release of enrgy from it

 

[ehild]

How does that energy come from. Due to potential energy or what?
And by the effect of energy release on charge i mean if the chrge is decresed or increased due to release of enrgy from it

Electric discharge happens between two objects if there is high enough potential difference between them. If there is potential difference, there is electric field. The electric field exerts force on charged particles in the air, they move which means electric current. Moreover, the electric field can be so strong, that it rips off electrons from atoms and more charged particles appear. These particles accelerate in the electric field, and can get so much energy that they ionize other atoms. As the result, there are a lot of ions, accelerated to high speed and moving towards one of the electrodes-positive particles to the negative electrode, and negative particles towards the positive one That moving charge means current, and it can be quite big. The particles moving with high speed collide with other particles, and share their energy. The increased average energy of the gas atoms means high temperature, and lot of atoms get in exited state. At high temperature, the gas expands - explodes, you hear sound. The excited atoms emit radiation -you see light.