SCI02 CO4.3

• Acceleration


  In physics, the rate of change in an object's velocity with respect to time
• Acceleration is defined as the rate of change in an object's velocity with respect to time
• Velocity changes when there is a change in speed and/or direction
• An object that is speeding up, slowing down, or changing its direction is accelerating
• Example problem: Calculate the acceleration of a car


  1. Step 1: Identify what is required

  2. Step 2: Identify the given

  3. Step 3: Write the working equation

  4. Step 4: Substitute the given values

  5. Step 5: Find the answer
• Motion graphs


  • Position vs time (x-t) graph
  • Velocity vs time (v-t) graph
• Constant velocity


  Objects with zero acceleration have constant velocities
• Constant acceleration


  Objects that are constantly accelerating change their velocities at the same rate over time
• The everyday usage and the physics usage of the term "acceleration" differ
• A car that moves from rest to a speed of 10 km/hr is said to be accelerating in everyday usage
• A moving car that suddenly stops or slows down is not accelerating in everyday usage