Finding spring constant for ball balanced between two springs

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dance_sg
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Homework Statement



A 7.50-kg ball is placed on top of a spring with a spring constant of 475 N/m that has an initial length of 35.0 cm (h1). When the ball has reached its equilibrium position, it is supported by both springs at a height of 20.0 cm above the table (h3). If the shorter spring has an initial length of 25.0 cm, what is its spring constant?

Homework Equations



f=-kx

The Attempt at a Solution


would i find the force for h1 then use that number and 25.0 cm (0.25m) to find the spring constant? or do i have to find the force of h1 and h2, add them up, then divide that nu,ber by0.25m to find k..
 
Is there a picture that goes with this? The description you gave is inadequate to help me figure out what is going on.
 
yes there is, i don't know how to upload the image tho. when i try it says invalid file type
 
When you reply to this thread, do you see the "Attach files" box under "Additional Options"?
Is your file one of "bmp doc gif jpe jpeg jpg m ms mw mws nb pdf png psd txt xls zip"? Is it perhaps too big?
 
im trying to make it work right now. i think it may!
 
i remade it on paint.
 
Attachments
  • Diagram of a ball on a spring above a black base, shown at its initial raised position labelled h1 and h2, and at a lower equilibrium position labelled h3 with the spring compressed.
    diagram.jpg
    8.9 KB · Views: 464
OK, I think I understand now. One spring supports the 7.50-kg ball when it is compressed by 0.15 m. The other spring supports the 7.50-kg ball when it is compressed by 0.05 m.

Draw a free body diagram, put in all the forces and find an expression for the distance by which the spring is compressed in terms of the ball's weight and the spring constant.