JEE Mains · Physics · STD 11 - 6. system of particles and rotational motion
Consider a circular disc of radius 20 cm with centre located at the origin. A circular hole of radius 5 cm is cut from this disc in such a way that the edge of the hole touches the edge of the disc. The distance of centre of mass of residual or remaining disc from the origin will be ________.
- A 2.0 cm
- B 1.5 cm
- C 1.0 cm
- D 0.5 cm
Answer & Solution
Correct Answer
(C) 1.0 cm
Step-by-step Solution
Detailed explanation
\(\text { mass of disc }=\mathrm{m}\) \(\text { mass of cut part }=\frac{m}{16}\) \(X_{c o m}=\frac{m \times 0-\frac{m}{16} \times 15}{m-\frac{m}{16}}\) \(=1 \mathrm{~cm} .\)
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