# Ch 3: AP Physics C: Direct Current Circuits

### About This Chapter

## AP Physics C: Direct Current Circuits - Chapter Summary and Learning Objectives

Maybe what you know about electricity stops at the wall outlet, but in this chapter, you can learn about current, voltage, resistance, and more. Our instructors have divided this chapter into smaller lessons, so you can learn about circuits one video at a time. You'll see how electric circuits work, their component parts, and how to categorize different types. You'll learn how to make calculations about current, voltage, and other measurements in circuits. After completing this chapter, you should be able to:

- Define and name the units of voltage, current, and resistance
- Explain how current flows through a circuit
- Identify the components of a circuit
- Describe the relationship between current and voltage

Video | Objective |
---|---|

What is Electric Current? - Definition, Unit, and Types | Learn about the movement of electrons, or current, and how it's measured. |

Electrical Resistance: Definition, Unit, and Variables | Understand the levels of resistance a substance can have against a current. |

Electric Circuit Fundamentals: Components and Types | See the parts of an electric circuit and learn the role of each. |

Circuit Analysis | Explore circuits to see how to find voltages and currents within a group of components. |

Combining Resistors: Series and Parallel | Study these two types of resistors and the ways they can be combined. |

Kirchhoff's Rules | Examine these equalities that relate current and voltage within electric circuits. |

Resistance: Capacitance (RC) Circuits | Take a look at this type of circuit that has combinations of resistors and capacitors. |

### 1. What is Electric Current? - Definition, Unit & Types

Electrical current involves the flow of charged particles, or electrons, and it is an integral part of electricity. In this lesson, we will dive into the definition of current, as well as the unit and types to understand just how electricity moves.

### 2. Electrical Resistance: Definition, Unit & Variables

Electrical resistance refers to the force that impedes electrons in an electrical current flowing through a conductor. Explore the causes of electrical resistance, the various factors that can affect the resistance of different objects, as well as the practical applications of objects with high resistance.

### 3. Electric Circuit Fundamentals: Components & Types

Electric circuit fundamentals include components of two types of circuits. Explore the differences between series and parallel circuits and how voltage, total resistance, and current are affected in each type of circuit when more resistances are added.

### 4. Series Circuits: Definition & Concepts

A series circuit is a circuit that has only one path in which current can flow, going through each component. Learn about circuit pathways and the concept behind a single pathway, explore the definition of a series circuit, and understand the relation of resistance and voltage to the current in a series circuit.

### 5. Parallel Circuits: Definition & Concepts

A parallel circuit possesses different branches and paths where the current can flow. Understand the definition of a parallel circuit, and explore relevant concepts such as the pathways and resistance in this type of circuit, as well as Ohm's law.

### 6. Finding the Equivalent Resistance: Series, Parallel & Combination Circuits

Equivalent resistance refers to the cumulative resistance existing throughout all parts of a circuit system. Learn about series circuits, parallel resistance, and combination circuits relating to equivalent resistance.

### 7. Applying Kirchhoff's Rules: Examples & Problems

Gustav Kirchhoff developed two rules to analyze currents and voltage in complex circuits. Learn how to apply Kirchoff's rules, discover how to use the current and voltage rules, and review examples and problems of each.

### 8. Resistor-Capacitor (RC) Circuits: Definition & Explanation

A resistor-capacitor (RC) circuit is a type of circuit configuration that is composed of resistive and capacitive elements. Learn more about RC circuits, capacitors, and resistors, explore their combination in a circuit, and understand decay in an RC circuit.

### 9. Resistor-Capacitor (RC) Circuits: Practice Problems

Practice how to solve problems involving resistor-capacitor circuits. Discover what an RC circuit is, how to solve RC circuit equations, and practice solving some example problems.

### 10. What is a Voltmeter? - Definition & Uses

A voltmeter is a device used to measure the electric potential difference between two points or nodes in a circuit. Learn more about the definition of a voltmeter and discover its common uses.

### 11. What is an Ammeter? - Definition & Function

An ammeter is a tool for measuring electrical current that got its name from ampere, which is the standard measurement for electrical current. Learn the definition and function of an ammeter and discover how it is used to measure both parallel circuits and series circuits.

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### Other Chapters

Other chapters within the AP Physics C - Electricity & Magnetism: Exam Prep course