Question

Three point masses $m_1,m_2$ and $m_3$ are placed at the corners of a thin massless rectangular sheet $(1.2m\times 1.0m)$, as shown. Centre of mass will be located at the point ?

• A. $(0.8,0.6)m$
• B. $(0.6,0.8)m$
• C. $(0.4,0.4)m$
• D. $(0.5,0.6)m$

Answer 1

The correct option is C $(0.4,0.4)m$

REF.Image.

$x=\frac{m_1{x}_1+m_2{x}_2+m_3{x}_3}{m_1+m_2+m_3}$

$=\frac{1.6\left(0\right)+2\left(0\right)+2.4\left(1.2\right)}{1.6+2+2.4}$

$=0.4$

$y=\frac{m_1{y}_1+m_2{y}_2+m_3{y}_3}{m_1+m_2+m_3}=\frac{1.6\left(0\right)+2\left(1\right)+2.4\left(0\right)}{1.6+2+2.4}$

$=0.4$

$\therefore (x,y)=(0.4,0.4)$