 Acceleration- Change in Velocity

Presentation on theme: "Acceleration- Change in Velocity"— Presentation transcript:

Acceleration- Change in Velocity
occurs when an object ______________ in speed. occurs when an object __________ in speed. occurs when an object _____________________

Types of acceleration Increasing speed Decreasing speed
Example: Car speeds up at green light Decreasing speed Example: Car slows down at stop light Changing Direction Example: Car turns screeeeech

How can a car be accelerating if its speed is a constant 65 km/h?
Question 1 How can a car be accelerating if its speed is a constant 65 km/h? _______________________________________

Calculating Acceleration
Acceleration = Final speed – Initial speed Time

Calculating Acceleration
Acceleration = 16m/s - 0m/s 4s Acceleration = _______ 0 s 1 s 2 s 3 s 4 s 0 m/s 4 m/s 8 m/s 12 m/s 16 m/s

Question 2 a = m/s – m/s a = ____ a = __________ s
A skydiver accelerates from 20 m/s to 40 m/s in 2 seconds. What is the skydiver’s average acceleration? a = m/s – m/s s a = ____ a = __________

Graphing Acceleration
Can use 2 kinds of graphs Speed vs. time Distance vs. time

Graphing Acceleration: Speed vs. Time Graphs
Speed is increasing with time = accelerating Line is straight = acceleration is constant

Graphing Acceleration: Speed vs. Time Graphs
Rise = 4 m/s Run = 2 s In Speed vs. Time graphs: Acceleration = Rise/Run = 4 m/s ÷ 2 s = ________

Graphing Acceleration: Distance vs. Time Graphs
Curved line means the object is accelerating. Your speed is increasing. Remember slope = speed.

Question 3 How is the speed of the car changing?
Run = 3 s Rise = -6 m/s How is the speed of the car changing? (speeding up, slowing down, or staying the same) __________________________ 2) What is this car’s acceleration? __________

Question 4 Which line(s) represents an object that is accelerating? ________________________________ Which line(s) show positive acceleration? ________________________________ 3) Which line(s) show negative acceleration? 4) Which line(s) show constant acceleration? _________________________________