Prob C151 RC Hibbeler C152 The steel wrecking ball is suspe

Prob. C15-1 (© R.C. Hibbeler) C15-2. The steel wrecking \"ball\" is suspended from the boom using an old rubber tire A. The crane operator lifts the ball then allows it to drop freely to break up the concrete. Explain, using appropriate numerical data, why it is a good idea to use the rubber tire for this work. Prob. C15-2 (© R.C. Hibbeler)

Solution

Rubber tire is used mainly works as a shock absorber. When the steel ball hits the target (here Concrete), then it swings/move about end of crane arm. The energy of that swing is mostly dissipated into the target but also into the cable and cable connectors as the ball bounces back. That shock of the impact resonates and gets dissipated by the tire. It reduces wear and tear on the cable and cable connectors, also on the crane tower.

the equation used are:

Final veloctity of ball before hitting the ground, v = u+gt

Energy dissipation is given by conservation of energy:

Energy dissipated = (1/2)*m*v^2