Young's modulus is given by Y=AΔLFL, here, A is cross-section area and ΔL is change in length.
Now, when force F is applied, change in length ΔL1=AYFL=πr2YFL=5cm
Now, when force 4F is applied, change in length
ΔL2=π16r2Y4F4L=πr2YFL=5cm
A wire of length L and radius r is clamped rigidly at one end. When the other end of the wire is pulled by a force F, its length increases by 5cm. Another wire of the same material of length 4L and radius 4r is pulled by a force 4F under same conditions. The increase in length of this wire is _____ cm.
Held on 25 Jul 2022 · Verified 6 Jul 2026.
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