Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Audio power wikipedia , lookup
Power electronics wikipedia , lookup
Electronic engineering wikipedia , lookup
Index of electronics articles wikipedia , lookup
Wireless power transfer wikipedia , lookup
Rectiverter wikipedia , lookup
Switched-mode power supply wikipedia , lookup
Chapters 17/18 Circuits Unit Electrical Power Electrical Energy Kirchoff’s Rules Electrical Power Power is the rate at which work is done In mechanics P = For Electrical Power W t P = VI = I2R V2 = R To get max power, would you make a series or parallel circuit? Why? Power Example A potential drop of 50 volts is measured across a 250 resistor. What is the power developed in the resistor? Power Example #2 Which circuit uses the greatest power? Think about this… V2 P = R Electrical Energy The amount of electrical energy used is equal to the work done on an electrical component For mechanics: W = Fd For electrical energy: V2t w = Pt = VIt = I2Rt = R Electrical Energy Example An Electrical heater draws a current of 8 amps and has a resistance of 15 . How much energy does the heater use in 1 minute? Kirchhoff's First Law The algebraic sum of the currents flowing through a junction is zero. Generally speaking, it says, the total current entering a junction must equal the total current leaving the junction. 10A 20A 3A ?? Kirchhoff's Second Law The algebraic sum of the potential differences in a circuit loop must be zero. Generally speaking, it says, around any loop in a circuit, the voltage rises must equal the voltage drops Junction Practice Problem How much current must be flowing out the other wire? 10 A 6A