**Conduction is a mode of heat transfer in which the heat is transferred from one part of the body by direct contact between the molecules, there is no movement of molecules, they stay in a fixed position but transfer the heat by vibrating. **

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### Fourier’s law :

**Fourier’s Law states that : The rate of heat transfer through a material is proportional to the negative gradient of temperature and the area through which the heat is flowing.**

**Q=− k ∇T**

**𝑞 is the heat flux vector, representing the rate of heat transfer per unit area (W/m²).***k*is the thermal conductivity of the material (W/m·K), a property that indicates how well the material conducts heat.**∇***T*is the temperature gradient (K/m), indicating the rate of change of temperature with distance within the material.

## Applications of Fourier’s law

**Engineering and Design**: To calculate the heat transfer in building materials, electronic devices,Metals and machinery.**Geology**: To understand heat flow within the Earth’s crust.**Environmental Science**: To study heat transfer in the atmosphere and oceans.