Question

Determine the tension developed in the cable ab required to support the traffic light, which has a mass of 19 kg . take h = 3.5 m.

Answer 1

Only two forces acts on the traffic light: the tension T of the cable (upward) and the weight of the traffic light (downward). The weight is

`mg=(19 kg)(9.81 m/s^2)=186.39 N`
If the traffic light is at equilibrium, the resultant of the two forces must be equal to zero (Netwon's second law):

`T-mg=0`
Therefore the tension of the cable is

`T=mg=186.39 N`