Picture #1:
• Acceleration: change in velocity compared with the time it takes to change 
 - Average Acceleration: (Final Velocity - Starting Velocity) / Time 
• Velocity: expressed in meters per seconds (m/s)
• Time: expressed in seconds (s)
• Acceleration is measured in meters per second per second
 - meters per second squared (m/s²)
Picture #2:
• Acceleration is a vector
 - magnitude 
 - direction
• Acceleration: increases and decreases in speed 
• Positive Acceleration: increase in speed 
 - sliding down from a hill
 - small velocity -> large velocity
• Negative Acceleration: decrease in speed 
 - car slowing then
 - high velocity -> low velocity
 - initial velocity is larger than final velocity
 - (v2 - v1) will be negative 
 - acceleration “a = (v2 - v1) / t” will be negative 
• Acceleration and velocity (rate of motion) in the same direction = speed will increase. 
• Acceleration and velocity in opposing directions = speed will decrease
Picture #3: 
• Acceleration: rate at which velocity changes
• Velocity is a vector: has magnitude & direction 
 - magnitude or direction changes = the velocity changes
• Object accelerates speed = direction of motion or both magnitude and direction changes 
• Acceleration depends on amount of time for the change to take place and how much velocity changes 
 - Small change in velocity can be a large change in acceleration if the change occurred quickly.
 - Large change in velocity can be a small change in acceleration if the change occurred slowly.
- Increasing speed by 5 m/s in 5 seconds is smaller acceleration to increase speed by 5 m/s in 1 second.
Picture #4: 
• An object changing the direction of motion experiences acceleration even when not speeding up or slowing down
• An object is always turning.
• Centripetal Acceleration: acceleration in circular mode.