Chapter 10 DC Circuits

Describe emf

Voltage created by a power source

State the units of emf

Volt

Describe the qualities of an ideal battery

High energy and power density, long life, and low resistance

Account for the internal resistance of a non-ideal battery

E - Ir

State the relationship of the currents through resistors in series

I1 = I2 = I3 = Itotal

Calculate the equivalent resistance of resistors in series

The sum of individual resistors

State the relationship of potential differences for resistors in parallel

Equal and the same as the total voltage source

Calculate the equivalent resistance of resistors in parallel

Add the reciprocals

State Kirchhoff's Loop Rule (Voltage Law)

Sum of all electric potential differences around any closed loop in a circuit is 0

Calculate potential difference across two points in a circuit

Set a reference of 0 and subtract

State Kirchhoff's Junction Rule (Current Law)

What goes into the junction must come out

Write the Loop Rule for any closed loop in a multi-loop circuit

Subtract resistors if they go along with the current and add voltages

Write the Junction Rule for any junction in a multi-loop circuit

I1 + I2 = I3

Describe the resistance of an ammeter and why

Little to no resistance to minimize voltage drop

Explain how to connect a voltmeter and why

Connected in parallel to the points you want to measure potential difference

Describe the resistance of a voltmeter and why

Ideally infinite to avoid voltage drop

Charging RC circuit: capacitor behavior at t = 0

Charge is 0, current is at its peak (Vs/R), acts as a short circuit

Charging RC circuit: capacitor behavior at t = infinity

Voltage is at peak and equal to Vs, current is 0, acts as an open circuit