Chapter 11: Motion

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Chapter 11 Motion

• Section 11.3
• Acceleration

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Acceleration

• The rate at which velocity changes is
  acceleration.
• Acceleration can be described as
• Change in speed
• Change in direction
• Change in both
• Acceleration is a vector.
• The SI unit for acceleration is m/s2.
• Constant acceleration is a steady change in
  velocity. (Think of an airplane taking off.)

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Calculating Acceleration

• For objects moving in a straight line
  acceleration can be found using the following
  formula
• Acceleration change in velocity
• Total time
• OR
• Acceleration (vf - vi)
• t

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More Calculations

• Acceleration can be positive or negative. (Think
  about speeding up or slowing down.)
• Solve
• A car traveling at 10 m/s starts to decelerate
  steadily. It comes to a complete stop in 20
  seconds. What is its acceleration?

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Graphs of Accelerated Motion

• The slope of a speed-time graph is acceleration.
• Constant acceleration is shown by a linear graph.
  
• If the slope is positive, the acceleration is
  positive.
• If the slope is negative, the acceleration is
  negative.