JEE Mains · Physics · STD 11 - System of particles and rotational motion
- JEE Mains 2026
- Easy
- MCQ
A uniform rod of mass m and length \(l\) suspended by means of two identical inextensible light strings as shown in figure. Tension in one string immediately after the other string is cut, is _________.(g acceleration due to gravity)

Pick an option to check your answer.
Answer & Solution
Correct Answer
(B) mg/4
Step-by-step Solution
Detailed explanation

\(mg \frac{l}{2}=\frac{ m l^2}{3} \alpha\)
\(\alpha=\frac{3 g}{2 l}\)...(1)
\(mg - T = ma _{ c }\)
\(T = mg - ma _{ c }\)
\(= mg - m \left(\frac{l}{2} \alpha\right)\)
\(= mg - m \left(\frac{l}{2} \cdot \frac{3 g}{2 l}\right)\)
\(T =\frac{ mg }{4}\)
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