Direct Current Circuits - Physics (Undergraduate Foundation)

This course covers the movement of electrical charges through circuits that do not change direction. You will learn the exact definitions of current, voltage, and resistance and how they relate through Ohm’s law. The syllabus explains resistivity in different materials, the electromotive force (EMF) provided by power sources, and the internal resistance of batteries. You will master the use of Kirchhoff’s rules to solve complex networks of resistors and power supplies. Mastering these principles is necessary for anyone building or fixing electrical devices and power systems. You will understand why certain wires heat up more than others and how to choose the right components for a circuit. These skills are used daily by electrical engineers, solar technicians, and hobbyists repairing household electronics or designing battery-powered gadgets. Practical knowledge of DC circuits ensures you can calculate power needs and prevent electrical failures in real-world projects. By the end of this course, you will be able to calculate current, voltage, and resistance in any part of a DC circuit using Ohm’s law. You will know how to determine the resistivity of a wire based on its material and physical dimensions. You will gain the ability to distinguish between terminal voltage and EMF while accounting for internal resistance. Most importantly, you will be able to apply Kirchhoff’s current and voltage laws to find unknown values in circuits with multiple loops and junctions. This course is for undergraduate students in engineering or science who need a solid foundation in electricity. It is also suitable for secondary school leavers preparing for university entrance exams or technical vocational training. Even for those not pursuing a degree, the course provides essential logic for electricians and tech enthusiasts who want to understand the science behind the tools they use. Anyone looking to move from basic guessing to precise electrical calculation will find this material vital.

Enrolment valid for 12 months

This course is also part of the following learning track. You may join the track to gain comprehensive knowledge across related courses.

PHY 102: General Physics II - Electricity and Magnetism

Electricity and magnetism run every home, factory, and phone all over the world. This track builds the technical foundation to master laws governing electrical energy and signals. You will progress from stationary charges to alternating current and electromagnetic waves. It simplifies the NUC CCMAS syllabus into actionable knowledge for solving practical technical problems. The programme is for first-year university and polytechnic students in engineering or physical sciences. It also serves school leavers preparing for university physics or technical entrance exams. Science teachers and technicians who need a solid refresher on core electrical principles will find the material direct and relevant to their work. You will learn to calculate electrical forces, design functional DC and AC circuits, and predict how magnetic fields drive motors and generators. You will master the use of Gauss's Law, Kirchhoff's rules, and Maxwell's equations to solve engineering challenges. Completing this track ensures success in PHY 102 exams and prepares you for a career in power systems, telecommunications, or renewable energy.

Course Chapters

1. Introduction

This chapter introduces the fundamental concepts of charge flow and the microscopic nature of electricity. You will understand how individual electrons contribute to the macroscopic current measured in everyday circuits. You will define electric current and its units; master the relationship between charge and time using calculus; explain the physical concept of drift velocity; and distinguish between current and current density.

Concept Overviews

5 Lessons

Problem Walkthroughs

3 Lessons

2. Ohm's Law

This chapter focuses on the quantitative relationships between current, voltage, and material properties. You will learn how geometry and temperature affect the efficiency of electrical conductors. You will apply Ohm's law to circuit components; calculate resistance using resistivity and wire dimensions; determine the effects of temperature on conductivity; and solve for power dissipation and energy transfer.

Concept Overviews

5 Lessons

Problem Walkthroughs

4 Lessons

3. DC Circuits

This chapter introduces the practical assembly of resistors and power sources. You will learn to distinguish between ideal batteries and real-world sources with internal limitations. You will master series and parallel reduction techniques; understand the difference between EMF and terminal voltage; and apply the maximum power theorem to optimise circuit performance.

Concept Overviews

5 Lessons

Problem Walkthroughs

4 Lessons

4. Kirchhoff's Rules

This chapter covers advanced circuit analysis for networks that cannot be solved by simple reduction. You will master the fundamental laws of conservation that govern every electrical loop and junction. You will apply Kirchhoff's current and voltage laws; solve simultaneous equations for multi-loop networks; and calculate potential differences between any two points in a complex circuit.

Concept Overviews

4 Lessons

Problem Walkthroughs

3 Lessons

5. Conclusion

This final chapter reviews the essential laws governing charge movement and circuit analysis. It synthesises the tools needed to design and troubleshoot real-world DC systems. You will summarise the core relationships between Ohm's law and Kirchhoff's rules and evaluate your ability to apply these methods to complex electrical problems.

Concept Overviews

1 Lesson