Question

A circular plate of diameter $a$ is kept in contact with a square plate of edge $a$ as shown. The density of the material and the thickness are same everywhere. The centre of mass of the composite system will be :

• A. inside the circular plate
• B. inside the square plate
• C. at the point of contact
• D. outside the system

Answer 1

The correct option is B inside the square plate

Given,

Density and Thickness of both plates are same,

We know,

Volume= Surface area $\times$ thickness

Mass=density $\times$ volume

Hence Mass $\propto$ Surface area

$M_{circle}<M_{square}$ as $\frac{\pi a^2}{4}<a^2$

Hence ,The centre of mass will be shifted inside the square plate due to its greater mass.

Hence option $\text{B}$ is the correct answer.