Tightrope walking is a spectacle activity usually performed for the amusement of an audience. It involves a performer who walks along a thin wire or rope usually from a great height. It is also called funambulism. The "tightrope walker" may sometimes use a pole to aid in balancing while walking the rope. For heightened drama, the walker may perform the feat without the precaution of a safety net. A tightrope walking act is common for circuses .An acrobat can balance if her center of mass is directly over her base of support. When the tightrope walker is on the ground with feet side by side, her base of support is wide in the lateral direction but short in the sagital direction. Therefore her sway is from front to back. On a tightrope the reverse is true and her sway is side to side. In both cases her ankle is the pivot point.
She may use a pole for balance or may stretch out her arms perpendicular to her trunk in the manner of a pole. This technique provides several advantages. It distributes mass away from the pivot point and moves the center of mass out. This reduces angular velocity because her center of mass is now swinging through a longer arc. It takes longer to sweep out the same angle because the center of mass has a longer distance to go. The result is less tipping. In addition the performer can also correct sway by rotating the pole sideways. This will create an equal and opposite torque on her body. Sometimes the pole is weighted and has a dip at the ends. This provides additional stability by lowering the center of mass。
