Best answer:
Johny, First, you have to realize that when you pull back the swing, you're actually lifting it higher than it's resting position. The difference in height represents potential energy because the swing can now fall back to its resting position. At the rest position all that potential energy you stored in...
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Best answer: Johny, First, you have to realize that when you pull back the swing, you're actually lifting it higher than it's resting position. The difference in height represents potential energy because the swing can now fall back to its resting position. At the rest position all that potential energy you stored in the swing by lifting it will be transformed to kinetic energy. So what you must first do is figure out how high the swing was lifted. You use trig to do that. One leg of the triangle formed by lifting the swing is the initial length of the swing's support (1.85 meters). You can find the adjacent leg by using the angle (37.8 degrees) and assuming you're forming a right triangle. I did the calculation and I found that the adjacent leg to the swing length is 1.46 meters. The difference between these legs is the height you've raised the swing which comes out to be 0.39 meters.So the swing will fall a distance of 0.39 meters. Now the potential energy stored in the swing is mgh, and that's equal to the kinetic energy it will obtain by falling. We can equate these two and get:
mgh = 1/2mv^2.........and, as you can see, we can eliminate the mass from each side of this equation which gives us:
gh = 1/2 v^2. and v will = sq. rt. of 2gh. That comes out to be 2.76 m/sec.
I hope this helps. I tried to make this as clear as I can.
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15 hours ago