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What is the drift velocity of electrons in a copper wire of diameter 1.628 mm carrying 20.0 A of current?   The density of free electrons is calculated to be 8.34 x 1028 electrons/m3.  The charge of an electron is -e (-1.60 x 10-19C).   If a copper wire of diameter of 2.304 mm is used, what is the drift velocity?  Why are the drift velocities you calculated MUCH less than the signal speed in the order of 108 m/s? (3 points).

Spheres of charge: A conducting sphere of radius 20.0 cm carries an excess charge of +15.0 µC, and no other charges are present. (k = 1/4

5 wires meet at a junction.  I1 (current 1) and I2 (current 2) are going into the junction.   I3 (current 3), I4 (current 4) and I5 (current 5) are coming out of the junction.  a) Using Kirchhoff’s first rule, write the current equation. (1 point)b) If I1 = 1.46 A, I2 = 3.25 A, I3 = 1.71 A, I4 = 2.1 A, what is the value of I5? (2 points).

How much energy is stored in a capacitor with capacitance of 12.0 μF with a 4.0 V potential difference (voltage) across it? (2 points)

Current density: If a current of 2.4 A is flowing in a cylindrical wire of diameter 2.0 mm, what is the average current density in this wire?

Dielectrics: A parallel-plate capacitor has a capacitance of 10 mF and is charged with a 20 V power supply. The power supply is then removed and a dielectric material of dielectric constant 4.0 is used to fill the space between the plates. What is the voltage now across the capacitor?

Which of the following is a reliable indicator of pet food quality?

When evaluating food allergies, procedures such as intradermal skin testing, blood tests, and saliva tests are not always reliable as they can yield __________________.

Multi Answer This vitamin has no dietary requirement because cats and dogs can synthesize it in the liver. An excess of this can cause calcium oxalate uroliths.

Regulates advertising claims about pet food to prevent false or misleading marketing.