Acceleration Motion Unit

Acceleration  objects that speed up, slow down, or change direction have accelerated Acceleration = change in velocity Interval of time a =  v = v f – v i  t t f t i  speeding up is a change in velocity and therefore is considered acceleration  a car traveling around a corner at constant speed also represents acceleration due to the change in direction. 2

Question  You are traveling on a bus at 25m/s. In two seconds, the bus accelerates to 30m/s. What is the acceleration? a =  v = 30 m/s - 25 m/s = 5m/s = 2.5 m/s 2  t 2s 2s  when speed increases, acceleration is positive.  when speed decreases, acceleration is negative (also known as deceleration) 3

Assignment  Acceleration problems (11-3)  Build an accelerometer

Velocity- Time Graphs  **** Slope on a velocity- time graph represents ACCELERATION *****

Uniformly Accelerated Motion  Is an object that increases its speed at a constant rate This represents an object accelerating uniformly. 6

a)slope = rise/run = b)slope = rise/run = c)slope = rise/run = d)slope = rise/run = e)slope = rise/run = 7

Non-Uniform Acceleration  this is when objects accelerate at different rates. Ex. Find the acceleration during the various intervals. 8

Assignment  Velocity- time graph (11-10)

Velocity-Time Graph  Is it still possible to find the displacement of the object?  The Area under the graph is the displacement Length X Width 10

Describe the motion? How do you find the displacement??

 Area and Displacement (12-8)  Displacement from Velocity- Time Graphs (12-10)