A solid copper cube and sphere, both of same mass and emissivity are heated to same initial temperature and kept under identical conditions. What is the ratio of their initial rate of fall of temperature? Which of the following gives the correct final result?
Options

Question

A solid copper cube and sphere, both of same mass and emissivity are heated to same initial temperature and kept under identical conditions. What is the ratio of their initial rate of fall of temperature? Which of the following gives the correct final result?

Options

G1 Physics · Accepted Answer

Use Stefan-Boltzmann law P=eσA(T⁴−Tₛ⁴), Wien's law λₘT=b, or Newton's law of cooling dθ/dt=−k(θ−θₛ), as applicable. Evaluating the given data/statements gives (6/π)¹ᐟ³. Therefore the correct answer is A.