Assuming Hooke's law to be valid
T∝(Δℓ)
T=k(Δℓ)
Let,ℓ0= natural length (original length) ⇒T=k(ℓ−ℓ0)
so, {T}_{1}=k({\ell }_{1}-{\ell }_{0})&{T}_{2}=k({\ell }_{2}-{\ell }_{0})
⇒T2T1=ℓ2−ℓ0ℓ1−ℓ0
⇒ℓ0=T2−T1T2ℓ1−T1ℓ2
The length of metallic wire is l1 when tension in it is T1. It is l2 when the tension is T2. The original length of the wire will be :
Held on 26 Feb 2021 · Verified 6 Jul 2026.
T1+T2T2l1+T1l2
2l1+l2
T2−T1T2l1−T1l2
T2−T1T1l1−T2l2
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