Programming Exercise. A simple algebraic expression can be used to predict the cooling time of a small sphere, such as a ball bearing or a plastic bead, by comparing the surface area and volume of the sphere to that of a sphere whose cooling time has been measured experimentally. Heat flux from a sphere is proportional to its surface area, A = 4πτ2, where r is the radius of the sphere. If the sphere does not have an internal temperature gradient, then the time for it to cool to a certain temperature, t2, is inversely proportional to the surface area to volume ratio of the sphere, where the volume is V =-πr3. Thus, for two spheres or radii r. re the cooling time for sphere 2, t2, can be calculated by the experimentally determined cooling time for sphere 1, ti.;: t2 t for sphere 1, t. t,-tien. A1/V Az/V2 Write and record a macro to calculate the cooling time of sphere 2 based on (1) the surface area of the sphere, (2) the volume of the sphere, and (3) the experimentally measured cooing time of a sphere of the same material First, do the calculation on the spreadsheet by creating a table and then filling in the numbers for a sphere of 0.005 m radius that cools in 2.3 s, and a sphere of the same material of 0.012 m radius. Use a Function macro to calculate t2 = t1 a. 1/V A2/V2 Sphere 1 Sphere 2 0.0050.012 Radius (m) Cooling Time (s)2.3 Record a Macro that creates the table b. c. Write a Macro (you may use a mix of record and write) that allows you to input the values for r 2, and t, using an InputBox, then fills in these values in the table, calculates t2, and then writes the result in the table.
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