Chapter 3: Two-Dimensional Kinematics

position vector

A natural way to describe the position of an object in more than one dimension is to define a _______ that points from the origin to the location of the object.

Position Vector Definiton

**Instantaneous velocity (2D Kinematics)**

**Instantaneous speed (2D Kinematics)**

**Instantaneous acceleration (2D Kinematics)**

**two-dimensional vector equations**

The definitions of velocity and acceleration are **____________**, each of which is equivalent to a set of two one-dimensional equations.

definition of velocity

**instantaneous velocity**

For the **______________ vector**, the magnitude is the speed (a scalar), and its direction is in the direction of motion (tangent to the path of the object).

**inertial reference frames**

For most problems that you will have to deal with, the two reference frames will be **_____________**, which means that they move with a constant velocity with respect to each other. 

Vector addition relates the position of an object relative to two different frames of reference

**Tangential Acceleration (a∥)**

Affects only the magnitude of the velocity vector.

**Radial Acceleration  (a⊥)**

Affects only the direction of the velocity vector.

**ω**

determines the sense of rotation

**magnitude of ω**

determines how quickly the r(t) vector rotates.

**Phase shift angle** (ϕ)

A parameter that determines the initial angle and thus the initial position.

**Nonuniform circular motion**

Refers to motion in a circular path with nonconstant velocity.