Question

why lamps are hollow

Answer 1

here yours answer ! lamps are hollow because of they can give woll hahahahahaha

Answer 2

$\huge\boxed{\texttt{\fcolorbox{red}{aqua}{Hey Mate}}}$

In the hollowing of lamps the reason involved is that it could cause it to emit light at a characteristic wavelength specific to the element in the lamp as the light passes over a burner to a special detector that measures emitted intensity.