Question

how do the patterns of diffracted light from the bulb and glowing hydrogen tube differ in appearance?

Answer 1

Light given off from a hot object, in this case an incandescent bulb containing a hot filament, emits colors that appear smooth and continuous in wavelength, producing a bell curve. By contrast a hydrogen tube emit colors at different places on the spectrum, rather than continuously. For a white light, green, red, and blue must emit.