eli5: How can a laser burn of rust without melting?

Question

I just saw a YouTube video by someone with 2000 W laser and now I wonder how can the laser not melt itself when compared to a lense bundeling sunlight its always said cannot get hotter than the sun itself?

In: Physics

Answer 1

Lasers do get hot, they have cooling systems. Small laser pointers can use passive air cooling. Powerful industrial lasera need active water cooling.