Velocity and Acceleration
Velocity Describes both speed and direction of an object. Describes both speed and direction of an object. How can an object have the same speed, but different velocities? How can an object have the same speed, but different velocities? --not moving in the same direction
Acceleration is the rate of change of velocity per unit of time Positive or negative Units: ex. Meters/second squared
Acceleration continued: Can occur three ways: Can occur three ways: 1. increase speed 1. increase speed 2. decrease speed 2. decrease speed 3. a change in a direction 3. a change in a direction
Acceleration: Positive: Positive: Its speeding up Its speeding up Negative: Negative: Its slowing down Its slowing down
Formulas Velocity: Velocity: v = d / t Acceleration: a = vf-vi / t a = vf-vi / t
Examples A car’s velocity changes from 0 m/s to 40 m/s in 10 seconds. Calculate the car’s average acceleration. A car’s velocity changes from 0 m/s to 40 m/s in 10 seconds. Calculate the car’s average acceleration. a = 40 m/s – 0 m/s divided by 10 s a = 40 m/s – 0 m/s divided by 10 s a = 40 m/s / 10s a = 40 m/s / 10s a = 4 m/s squared a = 4 m/s squared