r=L2Rx+R
For a small section
AF=Ydxdl
⟹∫0LdL=∫0Lπ[L2Rx×R]2YMgdx
ΔL=πYMg[−[L2Rx+R]0L1×2RL]
=3πR2YMgL
Lf=L+ΔL=L[1+3πR2Ymg]
A uniformly tapering conical wire is made from a material of Young's modulus Y and has a normal, unextended length L. The radii, at the upper and lower ends of this conical wire, have values R and 3R, respectively. The upper end of the wire is fixed to a rigid support and a mass M is suspended from its lower end. The equilibrium extended length, of this wire, would equal:
Held on 9 Apr 2016 · Verified 6 Jul 2026.
L(1+92πYR2Mg)
L(1+91πYR2Mg)
L(1+31πYR2Mg)
L(1+32πYR2Mg)
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