Velocity And Acceleration Velocity: Velocity: Both speed and direction of an object V=d/t. Acceleration: Acceleration: The rate at which velocity changes.

Acceleration

Speed and Vector A vector quantity has both magnitude (the amount of or how much of) and direction. Therefore Velocity is a vector. Speed however only has magnitude not direction.

Displacement and Velocity Distance is the total length of the actual path between two points. Displacement is the length and direction of a straight line between starting and ending points. Therefore displacement is a vector. Distance is the total length of the actual path between two points. Displacement is the length and direction of a straight line between starting and ending points. Therefore displacement is a vector. Chapter 9 Motion and Energy

The arrows are larger as the plane increases speed or accelerates, because the arrows represent the vector quantity.

Types of Acceleration Increasing speed: speed increases per unit of time Decreasing speed: speed Decreases per unit of time Changing Direction:turning or circles.

Equation for Acceleration Final Velocity-Beginning Velocity Time Fv-Bv t Beginning Velocity Final Velocity Time a =

Units m/s/s m/s/s or m/s 2

A car was traveling 10m/s and increased its speed to 20m/s in 2s. What was the car's acceleration? A car was traveling 10m/s and increased its speed to 20m/s in 2s. What was the car's acceleration? 1. 30m/s/s 2. 10m/s/s 3. 5mph 4. 5m/s/s 0 30

A car was traveling 10m/s and decreased its speed to 0m/s in 1s. What was the car's acceleration? A car was traveling 10m/s and decreased its speed to 0m/s in 1s. What was the car's acceleration? m/s/s 2. 10m/s/s 3. 9mph 4. 9m/s/s

A bowling ball was dropped from a building. It reached a speed of 19.6m/s in 2 seconds. What was the car's acceleration? A bowling ball was dropped from a building. It reached a speed of 19.6m/s in 2 seconds. What was the car's acceleration? m/s/s m/s/s 3. 18mph m/s/s

Graphing Acceleration

What is this a graph of? 1. Speed 2. acceleration

Importance of Slope and Motion The shapes of the distance vs. time graphs for constant velocity motion and accelerated motion (i.e., changing velocity) - reveal an important principle. The principle is that the slope of the line on a distance vs. time graph reveals useful information about the velocity of the object. Whatever characteristics the velocity has, the slope will exhibit the same (and vice versa). If the velocity is constant, then the slope is constant (i.e., a straight line). If the velocity is changing, then the slope is changing (i.e., a curved line). If the velocity is positive, then the slope is positive (i.e., moving upwards and to the right). This very principle can be extended to any motion conceivable. The shapes of the distance vs. time graphs for constant velocity motion and accelerated motion (i.e., changing velocity) - reveal an important principle. The principle is that the slope of the line on a distance vs. time graph reveals useful information about the velocity of the object. Whatever characteristics the velocity has, the slope will exhibit the same (and vice versa). If the velocity is constant, then the slope is constant (i.e., a straight line). If the velocity is changing, then the slope is changing (i.e., a curved line). If the velocity is positive, then the slope is positive (i.e., moving upwards and to the right). This very principle can be extended to any motion conceivable.