Determine the cost per kilowatt hour for the energy delivered by a typical alkaline 9-V “transistor” battery that costs $1.95 and is capable of delivering a current of 50 mA for a period of 10 hours. (For comparison, the approximate cost of energy purchased from electric utilities in the United States is $0.12 per kilowatt hour.)

P1.17.) A circuit element having terminals a and b has vab = 10 V and ina = 2 A. Over a period of 20 seconds, how much charge moves through the element? If electrons carry the charge, which terminal do they enter? How much energy is transferred? Is it delivered to the element or taken from it?

In the circuit shown in the diagram below, two thick wires connect a 1.5 volt battery to a Nichrome (NiCr) wire. Each thick connecting wire is 15 cm long, and has a radius of 10 mm. The thick wires are made of copper, which has 8.36e+28 mobile electrons per cubic meter, and an electron mobility of 0.00434 (m/s)/(V/m). The Nichrome wire is 5 cm long, and has a radius of 2 mm. Nichrome has 9e+28 mobile electrons per cubic meter, and an electron mobility of 7e-05 (m/s)/(V/m). What is the magnitude of the electric field in the thick copper wire? V/m What is the magnitude of the electric field in the thin Nichrome wire? V/m Copper Nichrome Copper

Answer the following questions: regarding LED