Inez is putting up decorations for her sister\'s quinceanera (fifteenth birthday
ID: 1274525 • Letter: I
Question
Inez is putting up decorations for her sister's quinceanera (fifteenth birthday party). She ties three light silk ribbons together to the top of a gateway and hangs a rubber balloon from each ribbon (see figure below). To include the effects of the gravitational and buoyant forces on it, each balloon can be modeled as a particle of mass 2.06 g, with its center 50.5 cm from the point of support. Inez rubs the whole surface of each balloon with her woolen scarf, making the balloons hang separately with gaps between them. Looking directly upward from below the balloons, Inez notices that the centers of the hanging balloons form a horizontal equilateral triangle with sides 27.0 cm long. What is the common charge each balloon carries?
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Explanation / Answer
Let Fe be the electrostatic force between one balloon and another. That force will be horizontal. Looking down from above, The horizontal force on any one balloon is the vector sum of the forces from the adjacent balloons. An equilateral triangle's angle is 60