Yes.
yes
noooooooooooooooooooooo . Of course a set of Xmas lights is a light source. Any electric light is a light source.
Light source, can be mirror or electric light.
Yes, a torch can be a source of both light and heat. The light is produced by the flame or the electric bulb, while the heat is generated by the burning fuel or the electric components.
Mostly hydro electric power
An unnatural light source is any source of light that is not produced by natural occurrences like the sun or a fire. Examples include electric light bulbs, neon signs, and LED lights.
Either, depending on the situation. If you look at it from far away, the light seems to come from a single direction, and can be simplified as a point-source. If you are very close, the light comes from different directions, and such a simplification is no longer correct.
Switch to a light source with a shorter wavelength.... Switch to a light source with a higher frequency
Filament is a thin part of incandescent bulb which is the source of electric light that electric current passes through and heated it until it produce light.
an electric current passed through it
Increasing the intensity of light or using a shorter wavelength light source can cause an electric current to flow in a photoelectric effect experiment. The energy of the photons should be increased to overcome the work function of the metal surface, allowing electrons to be ejected and generate a current.
The diagram shows an incandescent light bulb as the source of light. It consists of a tungsten filament that emits light when an electric current passes through it, causing it to heat up and glow.