Question

A 12.2 m crane weighs 18.0 kN and is lifting a 50.3 kN load. The hoisting cable (tension T1) passes

over a pulley at the top of the crane and attaches to an electric winch in the cab. The pendant cable

(tension T2) which supports the crane, is fixed to the top of the crane. Find the tensions in the two cables.

Answer 1

Solution.

Sum the moments about the base of the crane; Σ M = 0. 

$T_2cos35Lcos40 + T_1cos45Lcos40 - T_2sin35Lsin40 - T_1sin45Lsin40 - W(L/2)sin40 - T_1Lsin40 =0;$

$0.259T_2=43kN;\implies$ $T_2=166kN;$

Answer: $T_2=166kN;$