Speed and Velocity

Up Speed Velocity Velocity Changes

  

What are typical speeds of players on the field?
How fast are they running?		 Click the "Speed" button to make some measurements.
What is a player's velocity?  To find the player's velocity you must determine his speed and the direction in which he is moving. Click the "Velocity" button.  Work through various animations and measure velocities.
Physics gets interesting when velocities are changing. Click the "Velocity Changes" button.  Watch various video clips and determine if the velocity of a player is changing.

  Physics gets interesting when velocities are changing?  Why?

To change the velocity of a player or a ball, a force is required. 
The quicker the rate of change, the larger is the net force that is required to make this change.
Physicist call the rate at which the velocity is changing the acceleration.