Question

Electric bulb is Marked 60 watts 120 volt what is the resistance of filament of bulb

Answer 1

P = i V
60 = i (120)
i = .5 amps
V = i R
R =120/.5 = 240 Ohms

or
P = V^2/R
so
R = 120^2/60 = 240 Ohms