Q. Starting in the spring, fruit begins to grow on the outer end of a branch on a pear tree. Define how the center of gravity of the pear growing branch shifts all through the course of the summer.

Presume you are standing on a train, both feet together, facing a window. The front of the train is to your left. The train starts moving forward. To keep from falling, you slide your right foot out toward the rear of the train. Define in terms of torque how this action keeps you from falling over.