speed and acceleration

• Speed


  The distance an object has travelled per unit time
• Working out the average speed

  Divide the DISTANCE TRAVELLED by the TIME TAKEN
• Velocity


  The speed of an object in a particular direction
• Acceleration


  The change in velocity over unit time
• Calculating acceleration/deceleration


  Acceleration = (new speed - old speed) / time taken

  Deceleration is always a negative number
• Acceleration


  • When an aeroplane takes off, people get pushed back in their seats

  When you're in the air, you're going at a constant speed so you can walk around
• Deceleration


  The opposite of acceleration, where velocity decreases