When did James watt invent light bulb?

Answer 1

James Watt did not invent the light bulb. Thomas Edison is regarded by most people to have invented it. There were other similar ideas to the light bulb before Edison, however, it was his superior design and set up of entire electrical lighting systems that brought fame and popularity to his bulb.

James Watt, is responsible for giving us the unit of measuring power that is his name (watt). The unit is derived by extending on Ohms law, to include that Voltage (e) times Amperage (i) = power.