A certain lightbulb filament when hot has a resistance of205 %u03A9. The potential difference across the filament at acertain instant is standard household voltage, 120 V.
(a) What current is flowing through the bulb at that time?
(b) If thefilament of the bulb is a tungsten wire having a radius of475 %u03BCm, what is the magnitude of the currentdensity in the filament?