posted by Matt Will on .
three lamps connected to a 120-V AC (rms) household supply voltage. Lamps 1 and 2 have 75.0-W bulbs; lamp 3 has a 40.0-W bulb.
(a) For each bulb, find the rms current.
Irms, lamp 1 = A
Irms, lamp 2 = A
Irms, lamp 3 = A
(b) For each bulb, find the resistance.
Rlamp 1 = Ω
Rlamp 2 = Ω
Rlamp 3 = Ω
The lamps are in parallel and all have an applied voltage of 120 V (rms)
(a) Irms = P/V
where P is the lamp power rating in Watts.
(b) V^2/R = P for each lamp
R = V^2/P = 1.44*10^4/P ohms