Why is the following situation impossible? An inquisitive physics student takes a 100-W incandescent lightbulb out of its socket and measures its resistance with an ohmmeter. He measures a value of 10.5 Ω. He is able to connect an ammeter to the lightbulb socket to correctly measure the current drawn by the bulb while operating. Inserting the bulb back into the socket and operating the bulb from a 120-V source, he measures the current to be 11.4 A.

The cord from an appliance is too short to reach the wall outlet in your room. You have two extension cords to choose from. (a) Find the voltage drop in the first extension cord having a 0.0700 Ω resistance and through which 5.80 A is flowing. V(b) The second extension cord is cheaper and utilizes thinner wire. It has a resistance of 0.700 Ω and the current flowing through it is 5.80 A. By what amount does the voltage supplied to the appliance change when the first extension cord is replaced by the second? V

> Lightbulb A is marked "60.0 W 120 V," and lightbulb B is marked "100 W 120 V." These labels mean that each lightbulb has its respective power delivered to it when it is connected to a constant 120-V source. (a) Find the resistance of each lightbulb. Ω RA RB Ω = (b) During what time interval does 1.20 C pass into lightbulb A? S (c) Is this charge different upon its exit versus its entry into the lightbulb? Yes No Explain. This answer has not been graded yet. (d) In what time interval does 1.40 J pass into lightbulb A? S (e) By what mechanisms does this energy enter and exit the lightbulb? Explain. This answer has not been graded yet. (f) Find the cost of running lightbulb A continuously for 30.0 days, assuming the electric company sells its product at $0.110 per kWh. (

Three identical 100.0-W, 120-V lightbulbs are connected across a 120-V power source as shown in in the figure below. Assume that the resistance of each bulb is constant (even though in reality the resistance increases markedly with current). 120 V R₁ R₂ (a) Find the total power supplied by the power source. W = (b) Find the potential difference across each lightbulb. AV₁ AV₂ = AV₂ = Need Help? Read It R₂ V Master It