Final answer:
The thermal resistance of insulation on a circular pipe is higher for larger diameter pipes when the insulation thickness and type are the same, as larger pipes have a greater surface area which influences heat transfer.
Step-by-step explanation:
To answer the question regarding thermal resistance in insulation on a circular pipe, we need to consider the properties of the insulating material as well as the geometry of the pipe. The thermal resistance, often denoted as R-value, is given by the ratio of the insulation thickness (d) to the thermal conductivity (k), as described by the formula R = d/k. Furthermore, for a cylindrical object such as a pipe, the resistance to heat flow also depends on shape and size as well as the material used.In the case of pipes with the same insulation thickness and type, the thermal resistance is not the same for all pipes—it varies with the pipe diameter. This is because, for larger diameter pipes, there's a larger surface area for heat transfer. Consequently, for a pipe with a larger diameter compared to a smaller one, with the same material and thickness of insulation, the thermal resistance of the insulation is higher.In summary, while the material and thickness of the insulation dictate the base resistance through its R-value, the geometry—in this case, the diameter of the pipe—will influence the overall thermal resistance of the system.