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Drift velocity: A wire has a cross-sectional area of 0.10 mm2. If there are 4.0 × 1028 atoms per cubic meter in this wire, and if each atom contributes 2 free electrons, what is the drift velocity of the electrons when the current in the wire is 6.0 A? (e = 1.60 × 10-19 C)

Cylindrical capacitors: The capacitance per unit length of a very long coaxial cable, made of two concentric cylinders, is 50 pF/m. What is the radius of the outer cylinder if the radius of the inner one is 1.0 mm? (k = 1/4πε0 = 8.99 × 109 N ∙ m2/C2)

LRC series circuits: A 120-V rms voltage at 1000 Hz is applied to an inductor, a 2.00-μF capacitor and a 100-Ω resistor, all in series. If the rms value of the current in this circuit is 0.680 A, what is the inductance of the inductor?

Electromagnetic waves: Given that the wavelengths of visible light range from 400 nm to 700 nm, what is the highest frequency of visible light? (c = 3.0 × 108 m/s)

The 82 

Current: In a certain electroplating process gold is deposited by using a current of 14.0 A for 19 minutes. A gold ion, Au+, has a mass of approximately 3.3 × 10-22 g. How many grams of gold are deposited by this process?

How much charge does a 9.0 V battery transfer from the negative to the positive terminal while doing 28 J of work?

The voltage across the terminals of a 9.0 V battery is 8.3 V when the battery is connected to a 45

In proton-beam therapy, a high-energy beam of protons is fired at a tumor.  As  the protons stop in the tumor, their kinetic energy breaks apart the tumor’s DNA, thus killing the tumor cells. For one patient, it is desired to deposit 0.09 J of proton energy in the tumor. To create the proton beam, protons are accelerated from rest through a 9.0×103 kV potential difference. What is the total charge of the protons that must be fired at the tumor? 

Two 4.8 cm x 4.8 cm metal plates are separated by a 0.21 mm thick piece of Teflon. (Dielectric constant for Teflon (