Three identical spheres, each of mass M , are placed at the corners of a right angle triangle with mutually…

Three identical spheres, each of mass M, are placed at the corners of a right angle triangle with mutually perpendicular sides equal to 2 m (see figure). Taking the point of intersection of the two mutually perpendicular sides as the origin, find the position vector of centre of mass.

  1. $2(i^{ }+j^{ })$
  2. i^+j^
  3. 23i^+j^
  4. 43i^+j^

Solution

First, recall the formula of the center of mass of n particle system, 

\(r_{c m}=\frac{m_1 r_1+m_2 r_2+m_3 r_3+\ldots+m_n r_n}{m_1+m_2+m_3+. .+m_n}\)

xcom=M×0+M×2+M×03M=23

ycom =M×0+M+2+M×03M=23

So the position vector of center of mass is, 23i^+23j^.

Asked in: NEET 2020 (Phase 2)

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