A certain lightbulb filament when hot has a resistance of 205 Ω. The potential difference across the filament at a certain instant is standard household voltage, 120 V. (a) What current is flowing through the bulb at that time? (b) If the filament of the bulb is a tungsten wire having a radius of 475 μm, what is the magnitude of the current density in the filament?
please help! i got (a)0.585365854A (b)123.2349166A/m^2 and both of the answers are wrong and i dont know how. a million thanks!!