Velocity and Acceleration Ch. 2 Pg. 40 - 69

Objectives Use correct SI units to express acceleration. Describe and analyze motion in one dimension using equations for acceleration. Understand the relationship between acceleration, force, and velocity. Generate and interpret graphs and charts describing motion using velocity and acceleration.

Acceleration Acceleration measures the rate of change of velocity over time. Acceleration has magnitude and direction Depending on the direction, acceleration can be positive, negative, or zero (constant velocity)

Different ways to change V Car speeds up a v v screech! Car slows up a

Accelerations (continued) v v Car turns a In all three cases, v changes. Therefore these are all examples of accelerations

Acceleration

Acceleration aave = ∆v = vf - vi Average acceleration is the rate of change of velocity in a given time interval aave = ∆v = vf - vi ∆t = tf - ti (m/s) (m/s2) (s)

Example: A shuttle bus slows to a stop with an average acceleration of -1.8 m/s2. How long does it take the bus to slow from 9.0 m/s to 0.0 m/s?

The slope and shape of the graph describe the object’s motion

The slope and shape of the graph describe the object’s motion