A steel rod 2 m long ( = 1.2 10 -5 / C) is heated through 100 C. Its increase in length is:

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A steel rod 2 m long (α = 1.2 × 10-5 /°C) is heated through 100°C. Its increase in length is:

Answer: 2.4 mm.

A 1.2 mm
B 2.4 mm
C 3.6 mm
D 4.8 mm

Correct answer: B. 2.4 mm

Explanation: ΔL = LαΔT = 2 × 1.2×10-5 × 100 = 2.4×10-3 m = 2.4 mm.

During a phase change (melting or boiling), temperature stays constant while heat is absorbed entirely as latent heat (Q=mL); temperature only rises again once the substance is fully in its new phase.

Concept context

Temperature scales, thermal expansion, calorimetry, and the three modes of heat transfer including radiation laws.

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A steel rod 2 m long (&alpha; = 1.2 &times; 10<sup>-5</sup> /&deg;C) is heated through 100&deg;C. Its increase in length is:

Concept context

More Thermal Properties of Matter questions

A steel rod 2 m long (α = 1.2 × 10<sup>-5</sup> /°C) is heated through 100°C. Its increase in length is: