Center of mass of an inclined triangle

AI Thread Summary
The discussion focuses on calculating the center of mass (COM) of an inclined triangle, specifically a right triangle. The initial calculations for the lengths of edges and angles are presented, leading to a proposed COM location. There is confusion regarding the accuracy of the y-coordinate of the COM, with a suggestion that it should be 14.4 instead of the calculated value. The importance of using the intersection of the medians to find the COM is emphasized, along with a recommendation to utilize a provided formula for easier computation. The conversation highlights the need for precise calculations and methods in determining the COM of geometric shapes.
Karol
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Homework Statement


Where's the COM

Homework Equations


The COM of a right triangle is a third of an edge apart of the right angle vertex

The Attempt at a Solution


Edge AC: ##\frac{50}{\cos 20^0}=53.2##
Two thirds of edge AB: ##\frac{53.2\cdot 30^0\cdot 2}{3}=30.7##
One third of edge BC: ##\frac{53.2\cdot \sin 30^0}{3}=8.9##
Edge AO: ##\sqrt {8.9^2+30.7^2}=32##
$$\cos \alpha=\frac{30.7}{32}\rightarrow \alpha=16.1^0$$
$$\beta=(30^0-\alpha)+20^0=33.9^0$$
Now i refer to drawing B:
$$x_{COM}=26.5 \surd,\ y_{COM}=17.8 \otimes$$
 

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Are you trying to say that the value for xCOM is correct but yCOM is wrong?

yCOM is suppose to be = 14.4?

Now why aren't you taking the intersection of the medians to determine the point O which is the COM?
 
Last edited:
Karol said:

Homework Statement


Where's the COM

Homework Equations


The COM of a right triangle is a third of an edge apart of the right angle vertex
Your result is correct, but it would be easier to use the formula in the link, after having determined the coordinates of the vertexes.

http://www.mathopenref.com/coordcentroid.html
 
Thanks
 
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