JEE Mains · Physics · STD 11 - 6. system of particles and rotational motion
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)
- A mg/2
- B mg/4
- C mg/3
- D mg
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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