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Diver Dave
Sep 4, 2007, 05:22 AM
An object that weighs 20N is fastened by a cord to the bottom of an object that weighs 30N the 30N object is supported by a cord fastened to the ceiling. Find the tension in the upper cord and the lower cord.

Capuchin
Sep 4, 2007, 05:28 AM
Assuming the cords are weightless, the cords must be providing enough force to keep the weights held up against the force of gravity.

I don't know how to make it any clearer without giving the answer away.

What do you think the answers are and why? :)

Diver Dave
Sep 4, 2007, 05:34 AM
I'm really just trying to understand how to solve this type of problem I'm working on it right now though

Capuchin
Sep 4, 2007, 05:37 AM
Well, in order for things to be in equilibrium, the total downward force must equal the total upward force.

If you take both weights and the bottom cord as a single weight being held up by the top cord, then what must be the tension in that cord?
You can apply the same logic to work out the tension in the bottom cord i.e. take the top cord and the top weight as a single weight attatched to the ceiling and then what must be the tension in the bottom cord?

Diver Dave
Sep 4, 2007, 05:45 AM
Wow
That makes a lot of sense now haha