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Question 30838
JEE Physics · Hard

Elasticity, Thermal Expansion, Calorimetry and Heat Transfer: Linear Expansion MCQ

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Linear ExpansionHardQuestion 30838

Question

Railway track gap is kept at 20°C for expansion at 50°C. Track length 25 m (α = 1.2×10⁻⁵ /°C). Required gap is:
  1. A
    6 mm
  2. B
    9 mm
    Correct
  3. C
    12 mm
  4. D
    3 mm

Correct answer

9 mm

Explanation

ΔL = 25 × 1.2×10⁻⁵ × 30 = 9×10⁻³ m = 9 mm.

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