A light bulb has an illuminance of 19.9 lx at a distance of 2 m . What is the luminous flux of the bulb?

It is increased due to the doppler effect. (apex)

In atoms, the electron carries a negative elementary or unit charge; the proton carries a positive charge. the two types of charge are equal and opposite. in an atom of matter, an electrical charge occurs whenever the number of protons in the nucleus differs from the number of electrons surrounding that nucleus.