Do charges (static or moving) reflect light?

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Charges, both static and moving, can reflect light, with free electrons in materials like mirrors serving as a prime example. Sparks emit light due to the rapid heating of air, creating plasma that releases energy in the form of light. The movement and acceleration of charges, such as those in a spark, contribute to this emission. Additionally, the electric fields surrounding atoms also play a role; when atoms vibrate, they cause their electric fields to oscillate, producing light. Overall, the interaction of charges and their fields is fundamental to the emission and reflection of light.
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Do charges (static or moving) reflect light? If no, then how can we see a spark?
 
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A spark emits light, it doesn't have to reflect it to be seen.
 
Free charges indeed reflect light, and quite well. Look at a mirror - it is free electrons which reflect.

Charges also emit very well when they move with acceleration. That is why we see a spark, a flame, Sun, etc.
 
And what makes spark to emit light?
 
The spark heats up the air to tremendous temperatures (into a plasma), which then emit their energy as light.
 
Originally posted by think
And what makes spark to emit light?

Atoms are electric charges, right? Right. They have electric field around them. When you shake an atom (say, atom is fast thermal motion in a spark), then field begin to shake too. This shaking electric field is what we call "light".
 

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