on Tuesday, April 5, 2011

In diving, similar to gymnastics, the athlete wants to jump as high as they can in order to allow for maximum rotations and flips.  In diving however one loses the spring filled floor and replaces it with the diving board to give them more height. 

So just how much higher can one jump on a springboard than on the ground?

The answer found was almost twice as high according to this study.  It was found that a 150 lb person can jump 0.52m off the ground of 0.92m off of a diving board!   This was found by using a person who had a crouch height, the amount which the person bends down before jumping of 0.4m and a spring constant of 833N/m.   

In addition to this the diving board contains a fulcrum allowing the diver to essentially change the spring constant of the board, though they must also consider where they can get the best timing with the board.  If the diver moves the fulcrum closer to the tip of the board the spring constant is fairly large, and the board provides a higher resistance to force and decreases the depression of the board.  When the fulcrum however is moved closer to the stand of the board, the spring constant decreases, creating less resistance to force and a higher depression of the board. It was found in this study by decreasing the spring constant as much as possible the test subject was able to increase their jump height from 0.92m to 1.2 m!!  This means that if the diver has the board adjusted to the right spring constant and has the correct timing with the board they can more than double the height they could achieve on the ground.

In addition to the height achieved from the board alone the diver uses an approach with a hurdle before the take off of the dive.  The hurdle is a little jump up, then landing back on the board for the takeoff of the dive. This creates a larger force on the board, also increasing their height.  Then there is always the additional height of however high the board is above the water (1-10 m).  

No wonder when watching diving it seems as if they are flying and that they are able to achieve so many flips and twists before they enter the water.