6 天之前 · However, the brightness of a luminous device is measured in watts in life because of luminous intensity's dependence on power, which resulted in it being bonded to watt, the unit of power. 20 火 嘅 燈膽 / 20 火 嘅 灯胆 [Cantonese] ― 20 fo2 ge3 dang1 daam2 [Jyutping] ― 20- watt lightbulb. Short for 火星 (Huǒxīng, “ Mars ”).