Question: To solve this problem, we will use the principles of steady - state heat transfer in a solid sphere with uniform heat generation . 1

To solve this problem, we will use the principles of steady-state heat transfer in a solid sphere with uniform heat generation.1. Rate of Heat Transfer from the Sphere to the Surroundings (q):The heat transfer through the surface of the sphere can be expressed using Fourier's law of heat conduction. The heat transfer rate (q) can be calculated using the formula:q =-k * A *(dT/dr)Where:- k is the thermal conductivity (400 J/s.m.\deg C)- A is the surface area of the sphere (4** R^2)- dT/dr is the temperature gradient.Since we are at steady state, we can simplify this to:q = k * A *(T2- T1)/(r2- r1)To find the surface area (A):A =4** R^2=4**(0.05)^2=0.0314 m^2(approximately)Now, we need to calculate the temperature gradient. We can assume that the temperature difference is between T2 and T1, where T1 is the temperature at the outer radius (0.04 m) and T2 is the temperature at the inner radius (0.02 m).Using the given values:- T1=100\deg C- T2=110\deg C- r1=0.04 m- r2=0.02 mNow we can substitute these values into the equation for q.q =400*0.0314*(110-100)/(0.02-0.04)Calculating this gives us:q =400*0.0314*10/(-0.02)Since we are looking for the heat transfer rate, we need to take the absolute value:q =400*0.0314*10/0.02=6280 J/s2. Temperature at the Center of the Sphere (T_center):In a sphere with uniform heat generation, the temperature at the center can be determined by using the formula for the temperature distribution in a sphere:T(r)= T1+(T2- T1)*(r/R)+(B/(6*k))*(R^2- r^2)At the center (r =0), we have:T_center = T1+(T2- T1)*(0/R)+(B/(6*k))*(R^2)Since we don't have B (the rate of heat generation), we cannot calculate T_center directly without additional information. However, we will note that T_center will be influenced by B.3. Neglecting Heat Generated within the Sphere:If we neglect the heat generated within the sphere (meaning B =0), the temperature distribution would be linear between T1 and T2. In this case, the temperature at the center would be the average of T1 and T2:T_center =(T1+ T2)/2=(100+110)/2=105\deg CIn summary:a) The rate of heat transfer from the sphere to the surroundings is approximately 6280 J/s.b) The temperature at the center of the sphere, neglecting heat generation, would be 105\deg C.c) If we neglect the heat generated within the sphere, the temperature at the center would be 105\deg C.

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