JEE Mains · Physics · STD 11 - System of particles and rotational motion
- JEE Mains 2019
- Hard
- MCQ
A uniform rectangular thin sheet \(ABCD\) of mass \(M\) has length \(a\) and breadth \(b\), as shown in the figure. If the shaded portion \(HBGO\) is cut off, the coordinates of the centre of mass of the remaining portion will be

Pick an option to check your answer.
Answer & Solution
Correct Answer
(D) \(\left( {\frac{{5a}}{12},\frac{{5b}}{12}} \right)\)
Step-by-step Solution
Detailed explanation
\(x = \frac{{M\frac{a}{2} - \frac{M}{4} \times \frac{{3a}}{4}}}{{M - \frac{M}{4}}}\)
\( = \frac{{\frac{a}{2} - \frac{{3a}}{{16}} \times \frac{{3a}}{4}}}{{\frac{3}{4}}} = \frac{{\frac{{5a}}{{16}}}}{{\frac{3}{4}}} = \frac{{5a}}{{12}}\)
\(y = \frac{{M\frac{b}{2} - \frac{M}{4} \times \frac{{3b}}{4}}}{{M - \frac{M}{4}}} = \frac{{5b}}{{12}}\)
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