JEE Mains · Physics · STD 11 - 6. system of particles and rotational motion
An massless equilateral triangle \(EFG\) of side \('a'\) (As shown in figure) has three particles of mass \(m\) situated at its vertices. The moment of intertia of the system about the line \(EX\) perpendicular to \(EG\) in the plane of \(EFG\) is \(\frac{ N }{20}\, ma ^{2}\) where \(N\) is an integer. The value of \(N\) is

- A \(25\)
- B \(33\)
- C \(30\)
- D \(39\)
Answer & Solution
Correct Answer
(A) \(25\)
Step-by-step Solution
Detailed explanation
\(I =0+ m \left(\frac{ a }{2}\right)^{2}+ ma ^{2}\) \(=\frac{5}{4} ma ^{2}\)
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