I am a beginner in Physics so please bear with me and keep it as simple as you can.

From what I have learned, "charged particles emit electromagnetic radiation which includes light". So my question is that an object, say a pen, is visible to us even when it is neutral and from what I have learned, it does not emit radiation so we should not be able to see neutral objects such as this pen. But we do see neutral objects so how is this possible?

Thank you and I apologize if this is a "dumb" question.

• Atoms of an object might be neutral but they are still made of charged subatomic particles and those can emit radiation. Aug 5 '21 at 17:07
• It is the interaction of an object with light from a different source, for example the sun providing sunlight, that you "see". The object itself is not required to directly emit photons. In this way you can see contrast between differently absorbing objects. An emitting object would be visible even in the dark without another light source, but a non emitting wouldn't be visible in that case. Aug 5 '21 at 17:10
• @Hans Wurst, correct me if I am wrong but from what I understood is that non-emiting objects which we see "reflect" photons at certain frequency which produces visible light for us to see. Am I right? Aug 5 '21 at 19:27
• Imagine a hot piece of metal. It emits its own light despite being neutral. Because, as triatticus points out, neutral materials are still made of charged particles, which can individually interact with and produce photons. Aug 5 '21 at 21:40
• @Anubis Yes that happens too. There are a lot of things coming together. Neutral objects also can emit if energy is provided in some form and aren't limited to absorption or scattering. Having a net charge is not required for this. Aug 6 '21 at 7:09

Emitted light = $$k \cdot T^4$$, where $$k$$ is a constant.