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lizzyb

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**see-saw, force exerted up by pivot?**

A child weighing 36 N climbs onto the right end of a see-saw, little knowing that it is tired down with a rope at its left end. The see-saw is 2.8 m long, weighs 11 N, and is tilted at an angle of 25 degrees from the horizontal. The center of the mass of the see-saw is half way along its length and lies right above the pivot.

There are 5 questions total and I've sucesfully answered 4 of them so far yet this one is odd:

Q: What is the total positive force exerted upwards by the pivot?

I first tried simply adding the two weights together (47 N) but this was wrong; then I added the two forces regarding the torque plus the total weight of objects on the see saw (45.6779 *2 + 36 + 11), but again that was wrong. How do I put these together? thanx.