Welcome to this physics lecture on Two-Dimensional Kinematics! In this video, we dive into the graphical methods of vector addition and subtraction. You will learn how to visually represent vectors—which have both magnitude and direction—using arrows whose lengths are proportional to their magnitude.
We will walk through the popular head-to-tail method step-by-step, showing you exactly how to place the tail of a second vector at the head of the first to draw your total resultant vector. Follow along as we solve real-world displacement problems using a ruler and protractor, from calculating the path of a person walking north and east across city blocks to mapping out the journey of a woman sailing a boat to a dock at night.
We will also uncover the commutative property of vectors, visually proving that you get the exact same total displacement no matter which order you add your vectors together ($A + B = B + A$). Plus, you will learn the secret to vector subtraction—which is simply adding a negative vector that points in the exact opposite direction. Finally, we will show you how to multiply a vector by a scalar to change its length, and introduce the crucial concept of resolving a single vector into its perpendicular horizontal and vertical components.
Whether you are studying for college physics or just want to master the geometry of motion, this video will give you the practical problem-solving steps you need to succeed.
