# Regents Kinematics

Regents Physics is all about energy in the universe, in all its various forms. Here on Earth, the source of our energy, directly or indirectly, is the sun. Solar power, wind power, hydroelectric power, fossil fuels, we can eventually trace the origin of all energy on our planet back to our sun. So where do we start in our study of the universe?

Theoretically, we could start by investigating any of these types of energy. In reality, however, by starting with energy of motion (aka kinetic energy), we can develop a set of analytical problem solving skills from basic principles that will serve us well as we expand into our study of other types of energy.

For an object to have kinetic energy, it must be moving. Specifically:

If kinetic energy is energy of motion, and energy is the ability or capacity to do work (moving an object), then we can think of kinetic energy as the ability or capacity of a moving object to move another object.

But what does it mean to be in motion? A moving object has a varying position… its location changes as a function of time. So to understand kinetic energy, we'll need to better understand position and how position changes. This will lead us into our first major unit, kinematics, from the Greek word *kinein*, meaning to move. Formally, kinematics is the branch of physics dealing with the description of an object's motion, leaving the study of the "why" of motion to our next major topic, dynamics.

### Objectives

- Understand the difference between distance and displacement and between speed and velocity.
- Calculate distance, displacement, speed, velocity, and acceleration.
- Solve problems involving average speed and average velocity.
- Construct and interpret graphs of position, velocity, and acceleration versus time.
- Determine and interpret slopes and areas of motion graphs.
- Determine the acceleration due to gravity near the surface of Earth.
- Use kinematic equations to solve problems for objects moving at a constant acceleration in a straight line and in free fall.
- Resolve a vector into perpendicular components: both graphically and algebraically.
- Sketch the theoretical path of a projectile.
- Recognize the independence of the vertical and horizontal motions of a projectile.
- Solve problems involving projectile motion for projectiles fired horizontally and at an angle.

### Topics of Study

- Defining Motion
- Graphing Motion
- Kinematic Equations
- Free Fall
- Projectile Motion
- Crossword Puzzle
- Kinematics Quiz