Lines of a particular element appear at the same wavelength in both emission and absorption line spectra. true or false

Each atom emits or absors electromagnetic radiation, but only in some frequencies that are characteristic of its chemical element.  

Now, if we supply energy in the form of heat (thermal energy) to a certain element in its gas phase, this will be stimulated and its atoms will emit radiation in certain frequencies of the visible spectrum, which constitute its emission spectrum.  

If the same element, also in gaseous state, receives electromagnetic radiation, it absorbs in certain frequencies of the visible spectrum, precisely the same ones in which it emits when it is stimulated by heat. This will be its absorption spectrum.  

waves moving from a fast medium to a slow medium will experience a reflection as light travels more slowly than red light. total internal reflection occurs when the critical angle is.

b mirrors submit a iisner? e. for which optical devices does d sometimes have a positive value? o a a and b o b. a and c o c. b and d 0 d. b and cb