Last Minute Lecture

Magnetic Fields & Forces – Moving Charges & Currents Explained | Chapter 27 of University Physics Chapter 27 dives into how moving charges and currents generate and respond to magnetic fields. From the fundamental Lorentz force to real-world applications like mass spectrometers and DC motors, you’ll build the foundation for electromagnetism. Watch the full video summary on YouTube for demonstrations of magnetic forces and device applications. Fundamentals of Magnetism Magnetic fields arise from moving electric charges. Every magnet has a north and south pole—no isolated monopoles exist. In practice, charges create the field, then other moving charges feel a force within it. The Magnetic Field (B) The magnetic field B is a vector field measured in tesla (T), with lines forming closed loops from north to south poles. Field line density indicates strength, and a compass aligns with the local field direction. Magnetic Force on a Moving Charge The Lorentz force law ...

Electrical Properties of Materials — Chapter 18 Summary from Callister’s Materials Science and Engineering Chapter 18 of Materials Science and Engineering by William D. Callister, Jr. and David G. Rethwisch examines how materials interact with electric fields and current, focusing on the principles of conductivity, semiconduction, and dielectric behavior. The ability to control and manipulate electrical properties is central to modern electronics, energy systems, and sensor technologies. Watch the full podcast-style summary below, and subscribe to Last Minute Lecture for comprehensive, chapter-by-chapter study guides to essential engineering textbooks! Understanding Electrical Conduction Ohm’s Law: The foundational relationship (V = IR) linking voltage, current, and resistance in materials. Types of Materials: Conductors: Metals with free electrons in partially filled energy bands, allowing high conductivity. Semiconductors: Materials (like ...