Physics - Heat & Thermo Question with Solution | TestHub

PhysicsHeat & ThermoThermal ExpansionMedium2 minQB

PhysicsMediumsingle choice

Passage / Comprehension

Two freely expanding rods initially have lengths 100 cm and 80 cm, with constant linear expansion coefficients 20 × $1 0^{- 6}$ $K^{- 1}$ and 25 × $1 0^{- 6}$ $K^{- 1}$ respectively. Heat both by 200 K. Use the linear expansion model. This question is self-contained.

After heating, which statement is correct?

Options:

Answer:

Solution:

$L_{1} α_{1} = L_{2} α_{2} = 0.002 cm / K$ , so each rod grows by $0.002 (200) = 0.4 cm$ . Final lengths are 100.4 cm and 80.4 cm . Their difference remains 20 cm , but $\frac{100.4}{80.4} = 1.248756 \dots < \frac{100}{80} = 1.25$ . Thus C. \end{document}

Subject:PhysicsTopic:Heat & ThermoSubtopic:Thermal Expansion

⏱ 2mℹ️ Source: QB

Doubts & Discussion

Loading discussions...