Physics 1301A/B Lecture Notes - Lecture 3: Parabolic Trajectory, Projectile Motion, Circular Motion
Document Summary
Chapter #3: motion in two and three dimensions. Vectors: a vector is a quantity that has both magnitude and direction. In two dimensions it takes two numbers to specify a vector. A vector can be represented by an arrow whose length corresponds to the vector"s magnitude: position is a vector quantity. An object"s position is speci ed by giving its distance from an origin and its direction relative to each axis. Here, r1 describes a point 2. 0m from the origin at a 30 angle to the axis. Adding vectors: to add vectors graphically, place the tail of the second vector at the head of the rst vector. Their sum is then the vector from the tail of the rst vector to the head of the second vector. Here, r2 is the sum of r1 and r. Vector arithmetic: to multiply a vector by a scalar, multiply the vector"s magnitude by the scalar. For a positive scalar the direction is unchanged.