Temperature Alarm

A company is developing a temperature alarm, based on the schema below, that should close an electric circuit when the temperature rises above 150°C:

Temperature Alarm

  Linear coefficient of thermal expansion (x10-6K-1) Volumetric mass density (kg/m3) Melting point (°C)
Brass 13 8600 1000
Copper 17 8940 1100
Iron 11.8 7870 1500
Mercury 181 13540 -39
Polystyrene 70 1060 100
Steel 12 7800 1600

Based on available materials and their properties, choose materials for the temperature alarm that require the smallest temperature difference to do the task.

For Material 1:

For Material 2:


  • AI-resistant
  • Mechanical Engineering
  • Bimetal
  • Materials Properties
  • New
  • Public
  • Easy


Difficulty: Easy

Duration: 3 min

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