can someone plz tell me how to find the coordinates of center of mass using double integration(iterated integrals)?also plz give an example(for instance semi circular disc)?

Question

anonymous · Answer

someone plz help!!!!!!!!!!!!!!!!!!!!!!!!!!

anonymous · Answer

i think the formola goes like this $$\int\limits_{}^{}\int\limits_{}^{}\rho dm \div \int\limits_{}^{}\int\limits_{}^{}dm$$

anonymous · Answer

nope, its integral x pho dA http://people.usd.edu/~jflores/MultiCalc02/WebBook/Chapter_16/Graphics16/MI_5/Html16_5/16.5%20Applications%20of%20Double%20Integrals.htm

anonymous · Answer

ok thanks!!! but what is x here

anonymous · Answer

x is the coordinate of the element dA.

similarly integral y pho dA

anonymous · Answer

but how han i use it to find com of a semicircular disk

anonymous · Answer

http://cnx.org/content/m14120/latest/

anonymous · Answer

ok thanks very much but why isnt d double integral used here?

anonymous · Answer

coz by summetry x for com is zero. so, we need to do only for y

anonymous · Answer

ok so if we consider the case of a disc we have to use it r8?

anonymous · Answer

yes