Question

a hollow semi-circular section is as shown in fig. determine centroid of the shaded portion​

Answer 1

Answer:

( 0 , 8.03 )

Explanation:

let the coordinates of the centroid be ( a , b)

by symmetry of the section about y- axis a = 0

b ={ (0.5 π*100²)(400/3π) - (0.5 π*75²)(300/3π) - 50 *200*25} ÷ { 0.5π(100²-75²) + 50*200}

   = 135416.67 ÷ 16872.23

    = 8.026 mm

  centroid    = ( 0 , 8.03 )