JEE Mains · Physics · STD 11 - System of particles and rotational motion
- JEE Mains 2020
- Medium
- MCQ
The coordinates of centre of mass of a uniform flag shaped lamina (thin flat plate) of mass \(4\;kg\). (The coordinates of the same are shown in figure) are

Pick an option to check your answer.
Answer & Solution
Correct Answer
(D) \((0.75\; \mathrm{m}, 1.75\; \mathrm{m})\)
Step-by-step Solution
Detailed explanation
\(\mathrm{m}_{1}=3 \mathrm{kg}\)
\(\mathrm{m}_{2}=1 \mathrm{kg}\)
Mass of plate- 1 is assumed to be concentrated at \((0.5,1.5)\)
Mass of plate- 2 is assumed to be concentrated at \((1.5,2.5)\)
\(\mathrm{x}_{\mathrm{cm}}=\frac{\mathrm{m}_{1} \mathrm{x}_{1}+\mathrm{m}_{2} \mathrm{x}_{2}}{\mathrm{m}_{1}+\mathrm{m}_{2}}=\frac{3 \times 0.5+1 \times 1.5}{4}=0.75\)
\(\mathrm{y}_{\mathrm{cm}}=\frac{\mathrm{m}_{1} \mathrm{y}_{1}+\mathrm{m}_{2} \mathrm{y}_{2}}{\mathrm{m}_{1}+\mathrm{m}_{2}}=\frac{3 \times 1.5+1 \times 2.5}{4}=1.75\)
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