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Subject: Biotransport

4. Measuring thermal diffusivity Thermal properties such as thermal diffusivity need to be measured so that heat transfer can be studied using mathematical models. In an experimental setup to measure thermal diffusivity of some food material (minced red meat). a tube, that can be approximated as a long cylinder, is filled wath the material and cooled. The center temperature i1s measured to be 5C after 65 s. The initial temperature was 27C and the boundary temperature 0C. The diameter of the cylinder is 10 mm. What is the thermal diffusivity of the food material? If the time duration in the experiment needs to be reduced by 10%. keeping everything else the same. what must be the new diameter