
Acceleration of the system, a=93g=310ms−2
Now, for R we can write
30−T1=3×a
⇒T1=20N
Therefore, strain developed in wire B,
strain=Y stress =YAT1=2×10110.005×10−420
=2×10−4
Each of three blocks P,Q and R shown in figure has a mass of 3kg. Each of the wire A and B has cross-sectional area 0.005cm2 and Young's modulus 2×1011Nm−2. Neglecting friction, the longitudinal strain on wire B is _____ ×10−4. (Take g=10ms−2)

Held on 30 Jan 2024 · Verified 6 Jul 2026.
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