Examveda

The thermal diffusivities for solids are generally

A. Less than those for gases

B. Less than those for liquids

C. More than those for liquids and gases

D. More or less same as for liquids and gases

Answer: Option C

Solution (By Examveda Team)

Thermal diffusivity is defined as the ratio of thermal conductivity to the product of density and specific heat capacity at constant pressure.

It indicates how quickly a material can conduct thermal energy relative to its ability to store it.

Solids generally have much higher thermal conductivity compared to liquids and gases, and although their density and specific heat may also be higher, the conductivity dominates, resulting in higher thermal diffusivity.

Liquids and gases typically have lower thermal conductivity and, in many cases, similar or lower specific heat, which makes their thermal diffusivity values lower than that of solids.

Option A: Less than those for gases
Incorrect. Gases usually have very low thermal diffusivity.

Option B: Less than those for liquids
Incorrect. Liquids have lower thermal diffusivity than most solids.

Option C: More than those for liquids and gases
Correct. Solids, particularly metals, typically have higher thermal diffusivity than both liquids and gases.

Option D: More or less same as for liquids and gases
Incorrect. Thermal diffusivity varies significantly among solids, liquids, and gases.

Correct Answer: Option C: More than those for liquids and gases

This Question Belongs to Mechanical Engineering >> Heat And Mass Transfer

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Comments (5)

  1. Ayaz Ali
    Ayaz Ali:
    3 months ago

    Solid less than liaquat than gasses

  2. Magesh Raj
    Magesh Raj:
    5 years ago

    Solution and correct option doesn't match

  3. Shield 2103
    Shield 2103:
    5 years ago

    option c is wrong in question.. correct it..in your solution you mentioned correct one

  4. Sidda Ramesh
    Sidda Ramesh:
    5 years ago

    Thise is lesser then lequid and gasses

  5. Hassan Latif
    Hassan Latif:
    5 years ago

    NO THIS IS SMALLER

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