2.4 Acceleration

• average acceleration = change in velocity / change in time
• SI Units for accelerations are m/s^2
• there is acceleration when velocity changes magnitude, direction, or both
• Acceleration is a vector
• acceleration is the direction of the change in velocity, but not always in the direction of the motion
• deceleration is not the same as negative acceleration
• when an object comes to a stop, it's velocity = 0
• To find the instantaneous acceleration only using algebra, we pick an average acceleration representative to the motion
• greater acceleration, greater velocity
• average velocity = initial velocity + velocity/2
• position = initial position + average velocity * time
• velocity = initial velocity + acceleration(time)
• final velocity depends on how large the acceleration is and how long it lasts
• if acceleration is 0, then initial velocity = final velocity
• negative acceleration will increase negative velocity
• if acceleration has the same signs as velocity, the object is speeding up
• if acceleration has opposite sign as velocity, the object is slowing down