Question

18[E]) When a power source like a battery is connected to a circuit, an electric field pushes electrons within the conducting wires causing them to flow. The electric field exists due to an uneven build up of charge on the surfaces of the wires (called a surface charge gradient). In this set of problems we will explore a simple model of how this all comes about and emphasize the connection between source charges, electric fields, and voltage differences in the context of electric circuits.

A very small segment of the conducting wire in a circuit can be modeled as a circular ring of radius 1 mm. Consider two such rings surrounding the z-axis separated by a small distance 2 mm. Let's first suppose that both rings have the same charge density. What is the strength of the electric field on the z-axis at the midpoint between the two rings?

Correct, computer gets: 0 V/m

19[E]) If you used a voltmeter to measure the voltage difference between the centers of the two rings, what measurement would you read?

Correct, computer gets: 0 V

20[H]) Now suppose that a power source is plugged into the circuit and that after a brief moment, you measure the voltage difference between the centers of the two rings to be 1 mV. What is the difference between the charge densities on the two rings?

21[E]) What's the strength of the average electric field between the centers of the two rings?

22[H]) What is the strength of the electric field at the midpoint between the centers of the two rings?

I need solutions from 20 to 22

Answer 1

20) Here it is given that initially the charge density ofboth rings was same. Now as we connect a power source the charge densities on each ofthe ring will be same as they are having same properties. So the difference in charge densities ofboth of them will be zero. Answer: Zero