Mechanical Engineering - Heat Transfer, Refrigeration and Air Conditioning - Discussion

The correct answer is: iron.

Thermal diffusivity is a measure of how quickly heat spreads through a material. Iron has a high thermal diffusivity due to;

1. High thermal conductivity (ability to conduct heat).
2. High density.
3. Low specific heat capacity (ability to absorb heat).

Iron's thermal diffusivity is approximately 23.1 mm²/s, which is one of the highest among common materials.

The other options have lower thermal diffusivities:

- Lead: 0.24 mm²/s (due to its low thermal conductivity and high specific heat capacity).
- Concrete: 0.14 mm²/s (due to its low thermal conductivity and high specific heat capacity).
- Wood: 0.06 mm²/s (due to its low thermal conductivity and high specific heat capacity).

Note: Thermal diffusivity values can vary depending on the specific material grade, temperature, and other factors.

I think the highest thermal diffusivity is typically found in materials with high thermal conductivity and low heat capacity.

Among the given options, iron tends to have the highest thermal diffusivity.

For iron:

Thermal difference = k/(den*heat cap) = 46.33/(.26*.12) = 1484.93.

For lead:

Thermal diff = k/(den*heat cap) = 20.39/(.41*.032) = 1554.12.

HENCE LEAD is correct answer.

Thermal diff = thermal conductivity/density * heat capacity at constant pressure.

But what is the value of k for iron and lead.

Option is iron because k value is high out of given options.

Thermal diffusivity = k/heat capacity.

That is not the K value, it is Thermal Diffusivity 'ALPHA' value for lead is 23.46*10^-6.

Yes, lead is correct answer.

I agree with you @Govind Agrawal.

Iron K = 80w/mk.
Lead K = 35w/mk.

Iron is correct answer.

You are Absolutely right, thanks @Govind.

What is the k value of lead?