Two bodies each of mass 0.5 kg and specific heat 400 J kg⁻¹ K⁻¹ are joined by a rod of negligible heat capacity, length 0.4 m, cross-section 2 cm² and k = 200 W m⁻¹ K⁻¹. Find the time for their temper

Question

Two bodies each of mass 0.5 kg and specific heat 400 J kg⁻¹ K⁻¹ are joined by a rod of negligible heat capacity, length 0.4 m, cross-section 2 cm² and $k = 200$ W m⁻¹ K⁻¹. Find the time for their temperature difference to fall to half, in seconds.

Answer:

693

Solution:

$t = \frac{l m s ln 2}{2 k A} = \frac{0.4 \times 0.5 \times 400 \times 0.693}{2 \times 200 \times 2 \times 1 0 ^{- 4}} = 693$ s.

TestHub · Accepted Answer

t = 2 k A l m s ln 2 ​ = 2 × 200 × 2 × 1 0 − 4 0.4 × 0.5 × 400 × 0.693 ​ = 693 s.

Physics - Heat & Thermo Question with Solution | TestHub

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