Please note additional help sessions and comments on Quiz 2 are now posted on the Web site. Ohm's law is an empirical relationship stating that current flow is proportional to voltage, with the constant of proportionality called R . If we apply an electric field, where t is an atomic property of solids called mean time between collisions. If we substitute this into the expression for the current density J , we find c . This gives us a connection between behavior at the atomic level namely, the flow of electrons and the macroscopic properties of circuits.
Energy is provided by emf in a circuit.
With a simple emf providing a current through a resistor, we can track the gain and loss of potential energy as a charge dQ is moved through the circuit from a to d. Hence, power is just the rate at which charges lose potential energy in traversing a circuit. Kirchhoff's rules give us a way of handling such questions. Now, let us apply this same kind of logic to the circuit which has a resistance and a capacitor connected together. Use Kirchhoff's rules to calculate the change in potential as one goes around the circuit.