Y=AΔLFL
⇒Y=A(ℓ1−ℓ0)T1ℓ0=A(ℓ2−ℓ0)T2ℓ0
1=T2(ℓ1−ℓ0)T1(ℓ2−ℓ0)
T2ℓ1−T2ℓ0=T1ℓ2−T1ℓ0
(T1−T2)ℓ0=T1ℓ2−T2ℓ1
ℓ0=(T1−T2T1ℓ2−T2ℓ1)
JEE Main 2021 — Physics Mechanics
The value of tension in a long thin metal wire has been changed from T1 to T2. The lengths of the metal wire at two different values of tension T1 and T2 are ℓ1 and ℓ2, respectively. The actual length of the metal wire is:
Held on 20 Jul 2021 · Verified 6 Jul 2026.
T1−T2T1ℓ2−T2ℓ1
T1−T2T1ℓ1−T2ℓ2
2ℓ1+ℓ2
T1T2ℓ1ℓ2
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