Positive Acceleration

• 1). Determine the initial speed. For example, you look at your speedometer and your moped is traveling 18 kilometers per hour.
  
  
• 2). Multiply the speed in kilometers per hour by 10/36 to convert the speed to meters per second. In the example, 18 x 10/36 = 5. Your moped is traveling 5 meters per second.
  
  
• 3). Determine the final speed after a given period of time has passed. In the example, after 10 seconds you look at the speedometer and your moped is traveling 36 kilometers per hour.
  
  
• 4). Multiply the speed in kilometers per hour by 10/36 to convert the speed to meters per second. In the example, 36 x 10/36 = 10. Your moped is traveling 10 meters per second.
  
  
• 5). Subtract the initial speed in meters per second from the final speed in meters per second. In the example, 10 - 5 = 5.
  
  
• 6). Divide the difference of the final speed and the initial speed by the period of time during which the acceleration took place. In the example, 5/10 = 0.5. The average acceleration of your moped was 0.5m/s^2, or 0.5 meters per second per second.
  
  
• 7). Multiply the average acceleration in meters per second per second by 36/10 to determine the acceleration in kilometers per hour per second. In the example, 0.5 x 36/10 = 1.8. The average acceleration of your moped was 1.8 kilometers per hour per second.
  
  

Negative Acceleration

• 1). Determine the initial speed. For example, you look at your speedometer and your car is traveling 72 kilometers per hour.
  
  
• 2). Multiply the speed in kilometers per hour by 10/36 to convert the speed to meters per second. In the example, 72 x 10/36 = 20. Your car is traveling 20 meters per second.
  
  
• 3). Determine the final speed after a given period of time has passed. In the example, after 10 seconds your car has stopped at a light and is traveling 0 kilometers per hour. This equals 0 meters per second.
  
  
• 4). Subtract the initial speed in seconds from the final speed in seconds. In the example, 0 - 20 = -20.
  
  
• 5). Divide the difference of the final speed and the initial speed by the period of time during which the acceleration took place. In the example, -20/10 = -2 The average acceleration of your car was -2 m/s^2, or -2 meters per second per second.
  
  
• 6). Multiply the average acceleration in meters per second per second by 36/10 to determine the acceleration in kilometers per hour per second. In the example, -2 x 36/10 = -7.2. The average acceleration of your car was -7.2 kilometers per hour per second.