3.2 Notes - Acceleration

Part A

Objectives Describe how acceleration, time and

velocity are related. Explain how positive and negative

acceleration affect motion. Write equations for the displacement and

velocity of an object over time. Recognize and draw graphs of an objects

displacement and velocity verses time.

Acceleration

A change in velocity divided by time

Acceleration =Final velocity – initial velocity

time

a =t

V

Acceleration The SI unit for acceleration is…

Derived unit velocity (m/s)time (s)

m/s2

Acceleration Occurs anytime there is a change in velocity When you speed up or slow down When you change direction

Acceleration Can be positive, negative, or zero

Positive = Speeding up Negative = slowing down Zero = moving @constant speed

Important Formulas

Acceleration =Final velocity – initial velocity

time a =t

V

Speed =Distance

timev = d

t

Motion Graphs Displacement vs. Time Graph

Time on the x-axis Displacement on y-axis

The slope of the line represents the object’s velocity The direction of the line (upward or downward)

is the same as the direction of the velocity vector

Example A = B = C = D = E =

Velocity vs. Time Graphs Time is on the x-axis Velocity is on the y-axis

The slope of the line represents the object’s acceleration The area under the line is the object’s

displacement

Velocity vs. Time Graphs http://www.physics247.com/physics-home

work-help/motion-graphs.php