Question

A 450.0 N, uniform, 1.50 m bar is suspended horizontally by two vertical cables at each end. Cable A can support a maximum tension of 550.0 N without breaking, and cable B can support up to 300.0 N. You want to place a small weight on this bar.

1)What is the heaviest weight you can put on without breaking either cable?
2)Where should you put this weight?

Answer 1

Weight = 400 N

d = 0.28m

Step-by-step explanation:

∑Fy = 0 gives Ta + Tb - W - Wbar = 0.

W=Ta + Tb - Wbar = 550N + 300N - 450N = 400N

To find distance you need to use the net torque formula.

∑τ = 0 gives Tb(d) - W * d - Wbar * (
`(d)/(2)`)

τ = Force * distance

d =
`(Tb*(1.5) - Wbar(0.75))/(W)`

d = 0.28m