Answer to Question #68817 in Mechanics | Relativity for Lewis

Question

Hi, I'm wondering if any of you could help me to solve this mechanic / physics question. I would like to keep a ball of vines at about 30 lbs hanging and set it 3 feet from the ground, except a cable wire from ceiling is not an option. Any taker?

Answer 1

If we have spring with elastic coefficient k and a ball is hanging on it, then:

mg=kx

where x is displacement from equilibrium of spring.

If l is length between equilibrium of spring and the ground, then we have:

mg=k(l-3) ;m=30 lbs

Finally:

30g=k(l-3)