Center of Mass of Three Beads Equation

AI Thread Summary
The discussion revolves around calculating the center of mass for three beads positioned at the vertices of an equilateral triangle. The first bead has a mass of 150 g at the top vertex, the second bead has a mass of 55 g on the left, and the third bead has a mass of 85 g on the right. The equation for the horizontal position of the center of mass is provided, but it needs to be expanded to include the y-coordinate due to the two-dimensional nature of the problem. Participants emphasize the importance of including all masses in the equation and adhering to forum rules by demonstrating an attempt at a solution. The conversation highlights the necessity of proper notation and calculations in physics problems.
starJ9
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OP warned about not including an attempt at a solution

Homework Statement



Three beads are placed on the vertices of an equilateral triangle of side d = 1.8 cm. The first bead of mass m1 = 150 g is placed on the top vertex. The second bead of mass m2 = 55 g is placed on the left vertex. The third bead of mass m3 = 85 g is placed on the right vertex.

Write a symbolic equation for the horizontal position of the center of mass relative to the left vertex of the triangle.

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Homework Equations



xcm = m1x + m2x + m3x...+mnxn / Mn

The Attempt at a Solution

 
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Hello star! Welcome to PF. :)
Good start, this equation. Since we are dealing with three masses, you can stop at 3. But we are also dealing with two dimensions, so we need something similar for the y coordinate. And I think I am missing some brackets -- at least if ##M_n = \Sigma_i m_i##

Furthermore, PF rules dictate that you show an actual attempt at solution (otherwise we would be in trouble with all teachers all over the place). No problem in your case: just fill in some numbers to see what you get !
 
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