jBullet / Hello Physics Tutorial

Hi, i am quite new in jMonkey Engine / jBullet or Gamedevelopment, but maybe someone can enlight me a little bit. I wonder wheter it is possible to detect the distance to the middle of a blocksite when it gets hit by a cannonball. Nor i can find any events i can bind on, when a brick was hitted. Is there a wise guy for whom this questions are rediculous?