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Point masses $1,2,3$ and 4 kg are lying at the points $(0,0,0),(2,0,0),(0,3,0)$ and $(-2,-2,0)$ respectively. The moment of inertia of this system about $X$-axis will be
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$43 \mathrm{~kg}-\mathrm{m}^2$
Moment of inertia of the whole system about the axis of rotation will be equal to the sum of the moments of inertia of all the particles.
$I=I_1+I_2+I_3+I_4$
$\therefore I=m_1 r_1^2+m_2 r_2^2+m_3 r_3^2+m_4 r_4^2$
$I=(1 \times 0)+(2 \times 0)+\left(3 \times 3^2\right)+4(-2)^2$
$I=0+0+27+16=43 \mathrm{~kg}-\mathrm{m}^2$
$I=I_1+I_2+I_3+I_4$
$\therefore I=m_1 r_1^2+m_2 r_2^2+m_3 r_3^2+m_4 r_4^2$
$I=(1 \times 0)+(2 \times 0)+\left(3 \times 3^2\right)+4(-2)^2$
$I=0+0+27+16=43 \mathrm{~kg}-\mathrm{m}^2$
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