Consider a rectangular plate of dimensions `axxb`. If this plate is considered to be made up of four rectangles of dimensions `a/2xxb/2` and we now remove one out of four rectangles. Find the position where the centre of mass of the remaining system will lie?

Answer

A, B

Explanation

`x_(CM)=(A_1x_1-A_2x_2)/(A_1-A_2)`
`=((ab)(0)-((ab)/(4))(a/4))/(ab-(ab)/(4))`
`=-a/12`
`y_(CM)=(A_1y_1-A_2y_2)/(A_1-A_2)`
`=((ab)(0)-((ab)/(4))(b/4))/(ab-(ab)/(4))`
`=-b/12`