Question

A tower crane (Figure 1) must always be carefully balanced so that there is no net torque tending to tip it. A particular crane at a building site is about to lift a m = 3200-kg air-conditioning unit. The crane's dimensions are shown in (Figure 2). The crane's counterweight has a mass of M = 8000 kg . Ignore the mass of the beam.

Where must the crane's counterweight be placed when the load is lifted from the ground? (The counterweight is usually moved automatically via sensors and motors to precisely compensate for the load.)

Determine the maximum load that can be lifted with this counterweight when it is placed at its full extent.

Answer 1

Answers Balance torque on any point on the vertical pillar mx 7.7 Mxx 3200X7,7 = 8000XX X = 24640 8000 = 3,08 m. for maximum m, we can place Mal extreme position 8000 X 3,4 = mx7.7 m = 3532.5 kg 6 3.4m 5K 7.7M ma