Question

A tightrope walker in a circus holds a long flexible pole to help stay balanced on the rope. Holding the pole horizontally and perpendicular to the rope helps the performer.

• A. by lowering the overall centre-of-gravity.
• B. by increasing the rotation inertia.
• C. in the ability to adjust the centre-of-gravity to be over the rope.
• D. in achieving the centre of gravity to be under the rope.

Answer 1

Answer: (B), (C)

by increasing the rotation inertia.
in the ability to adjust the centre-of-gravity to be over the rope.

To attain the equilibrium in order to stay balanced the center of mass and center of gravity should locate over the support point(i.e. rope). Also, smaller the moment of inertia means less resistance to rotation (some rapid corrections have to made to achieve rotational equilibrium) the moment of inertia can be increased by stretching hands outside. Hence, holding the pole horizontally and perpendicular to the rope helps the performer to make balance by increasing the rotation inertia and the ability to adjust the center-of-gravity to be over the rope.