Suspended Painting: Finding Its Weight

[ignacioserra]

Homework Statement

A painting hangs from two identical silk ropes that form an angle of 120º. Both ropes make forces of 400 N each to keep it in place.

Homework Equations

a. Find the combined force of both silk ropes.(I have already done it)
b. How heavy is the painting?(need help in this one)

The Attempt at a Solution

I don't know what the Formula I have to use, to resolve the second one.

 

[LowlyPion]

Welcome to PF.

I think you will want to draw a picture yourself and resolve the forces on the ropes into x,y components.

Since everything is in equilibrium then the horizontal forces will cancel and be equal. The vertical force components then must support the weight.

 

[ignacioserra]

is the resultant of both forces equal to the weight?

 

[LowlyPion]

is the resultant of both forces equal to the weight?

That would be another way to do it.