Acceleration and accelerated motion

Acceleration and accelerated motion

1. Acceleration

   • Changes in speed and/or direction cause acceleration
     • Detecting velocity and acceleration
   • Average acceleration is velocity change over time
     • Units of acceleration
   • Acceleration can change with time or be constant
     • instantaneous and constant acceleration
   • Acceleration can be determined graphically
     • Velocity-time graph
   • Objects can accelerate or decelerate
     • when velocity and acceleration have opposite signs the speed decrease

2. motion with constant acceleration

   • Multiplying acceleration and time gives the change in velocity
     • Velocity-time equation
   • Average velocity is easy to calculate
     • when the acceleration is constant, the average velocity is equal to the sum of the initial and final velocities divided by 2
   • Average velocity is used in equations of motion
     • position-time equation with initial and final velocity
     • Position-time equation with average velocity
   • A velocity-time graph indicates distance traveled
     • the distance traveled by an object is equal to the area under its velocity-time curve
   • Position is related to accelerated and time
     • position-time equation for constant acceleration
   • Acceleration causes velocity to change with position
     • velocity-position equation

3. Position-time graphs for constant acceleration

   • Position-time graphs of accelerated motion are not linear
     • acceleration and curvature
   • Position-time graphs can track multiple objects
     • Position-time curves
   • Graphs can show acceleration and deceleration
     • apogee

4. Free fall

   • Freely falling objects have constant acceleration
     • Galileo Galilei
   • Many situations approximate free fall
     • air resistance
   • Freely falling objects are always accelerating
     • Gravity
   • Position and velocity change differently in free fall
     • Symmetry of motion
   • the acceleration due to gravity is denoted as g
     • Symbol g