Question

The distance of centre of mass of uniform circular disc of radius R, from the geometric centre on the axis of symmetry is

Answer 1

ANSWER

You have to need to me the fact that the centre of man of an uniform semi-circular circular ring of radius r lies at a vertical distance of place on

π

2R

axis on the centre. By symmetry the x− coordinate of centre of man is =0

x

un

=0

Now, we have to need to be certain things to find Y

un

. At a vertical distance Y from the origin imagine u infinite i mal disk with a thickness =dR

The area of that infiniteterimal disk is dA=πRdR

let's find out it's mass,

⇒dm=6dA

=πRdR×CR

2

=πCR

3

dR.

Y

r

is the position of the centroid of that dR ring and it equals =

π

2R

.