JEE Mains · Physics · STD 11- Mechanical properties of solids
- JEE Mains 2024
- Hard
- Numerical
Each of three blocks \(P\), \(Q\) and \(R\) shown in figure has a mass of \(3 \mathrm{~kg}\). Each of the wire \(A\) and \(B\) has cross-sectional area \(0.005 \mathrm{~cm}^2\) and Young's modulus \(2 \times 10^{11} \mathrm{~N} \mathrm{~m}^{-2}\). Neglecting friction, the longitudinal strain on wire \(B\) is _______ \(\times 10^{-4}\). \(\left(\right.\) Take \(\mathrm{g}=10 \mathrm{~m} / \mathrm{s}^2\) )

Pick an option to check your answer.
Answer & Solution
Correct Answer
(D) \(2\)
Step-by-step Solution
Detailed explanation
\( a=\frac{10}{3} \mathrm{~m} / \mathrm{s}^2 \)
\( 30-T_1=3 \times a \)
\( T_1=20 \mathrm{~N} \)
\( \text {strain }=\frac{\text { stress }}{Y} \)
\( =2 \times 10^{-4}\)

\( 30-T_1=3 \times a \)
\( T_1=20 \mathrm{~N} \)
\( \text {strain }=\frac{\text { stress }}{Y} \)
\( =2 \times 10^{-4}\)

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