18:49Root Mean Square (RMS) Voltage for Sinusoidal, Square ,and Sawtooth SignalsPhysics Ninja562views
16:11Intro to AC Circuits using Phasors and RMS Voltage and Current | Doc PhysicsDoc Schuster373views
Multiple ChoiceAn AC source operates with a 0.05 s period. 0.025 s after the current is at a maximum, the current is measured to be 1.4 A. What is the RMS current of this AC circuit?434views5rank1comments
Multiple ChoiceA person touches a wire carrying a 120 V AC voltage. One hand touches the wire, and both of the person's feet are bare and are touching the ground. Assume skin resistance at the hand and at each foot is 2200 Ω. What is the current through the person's torso?316views
Textbook QuestionYou have a special light bulb with a very delicate wire filament. The wire will break if the current in it ever exceeds 1.50 A, even for an instant. What is the largest root-mean-square current you can run through this bulb?221views
Textbook QuestionOff to Europe! You plan to take your hair dryer to Europe, where the electrical outlets put out 240 V instead of the 120 V seen in the United States. The dryer puts out 1600 W at 120 V. (a) What could you do to operate your dryer via the 240-V line in Europe?218views
Textbook QuestionOff to Europe! You plan to take your hair dryer to Europe, where the electrical outlets put out 240 V instead of the 120 V seen in the United States. The dryer puts out 1600 W at 120 V. (b) What current will your dryer draw from a European outlet? (c) What resistance will your dryer appear to have when operated at 240 V?215views
Textbook QuestionCommercial electricity is generated and transmitted as three-phase electricity. Instead of a single emf, three separate wires carry currents for the emfs ε₁=ε₀ cos ωt, ε₂=ε₀ cos(ωt +120°), and ε₃=ε₀ cos(ωt−120°) over three parallel wires, each of which supplies one-third of the power. This is why the long-distance transmission lines you see in the countryside have three wires. Suppose the transmission lines into a city supply a total of 450 MW of electric power, a realistic value. a. What would be the rms current in each wire if the transmission voltage were ε₀=120 V rms?201views
Textbook QuestionCommercial electricity is generated and transmitted as three-phase electricity. Instead of a single emf, three separate wires carry currents for the emfs ε₁=ε₀ cos ωt, ε₂=ε₀ cos(ωt +120°), and ε₃=ε₀ cos(ωt−120°) over three parallel wires, each of which supplies one-third of the power. This is why the long-distance transmission lines you see in the countryside have three wires. Suppose the transmission lines into a city supply a total of 450 MW of electric power, a realistic value. b. In fact, transformers are used to step the transmission-line voltage up to 500 kV rms. What is the current in each wire?212views
Textbook Question(II) If the current gain of the transistor amplifier in Fig. 40–49 is β = ic/iB = 95, what value must Rc have if a 1.0-μA ac base current is to produce an ac output voltage of 0.40 V?<IMAGE>40views
Textbook Question(II) An amplifier has a voltage gain of 75 and a 25-kΩ load (output) resistance. What is the peak output current through the load resistor if the input voltage is an ac signal with a peak of 0.080 V?47views
Textbook Question(II) An ac voltage of 120 V rms is to be rectified. Estimate very roughly the average current in the output resistor R (42 kΩ) for (a) a half-wave rectifier (Fig. 40–39), and (b) a full-wave rectifier (Fig. 40–40) without capacitor.<IMAGE>9views
Textbook QuestionShow that if the inductor L in the filter circuit of Fig. 30–33 (Problem 87) is replaced by a large resistor R, there will still be significant attenuation of the ac voltage and little attenuation of the dc voltage if the input dc voltage is high and the current (and power) are low.<IMAGE>9views
Textbook Question(III) A 120-V rms 60-Hz voltage is to be rectified with a full-wave rectifier as in Fig. 40–40, where R = 24 kΩ, and C = 35 μF. (a) Make a rough estimate of the average current. (b) What happens if C = 0.10 μF? [Hint: See Section 26–5.]<IMAGE>3views
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