An iron cube , of edge10 cm ,painted black is at a temperatureof 127^(@) C keptin aroom of tempeature27^(@)C. Ifthe densityand specific heat capacityof ironbe 7600 kg//m^(2)and 470 J// Kg - K , findthe initial rate of coolingof the cube.

An iron cube , of edge10 cm ,painted black is at a temperatureof 127^(

1.	An iron cube , of edge10 cm ,painted black is at a temperatureof 127^(@) C keptin aroom of tempeature27^(@)C. Ifthe densityand specific heat capacityof ironbe 7600 kg//m^(2)and 470 J// Kg - K , findthe initial rate of coolingof the cube.
Answer» <html><body><p></p>Solution :Here , area `A = 6a^(2) ` and volume`<a href="https://interviewquestions.tuteehub.com/tag/v-722631" style="font-weight:bold;" target="_blank" title="Click to know more about V">V</a> = a^(3) , a= <a href="https://interviewquestions.tuteehub.com/tag/10-261113" style="font-weight:bold;" target="_blank" title="Click to know more about 10">10</a> xx 10^(2)m ,e= 1 ` ( `because` the surfaceis painted black ). <br/> `rho = 7600 kg // m^(3) , s = 470 J.Kg - <a href="https://interviewquestions.tuteehub.com/tag/k-527196" style="font-weight:bold;" target="_blank" title="Click to know more about K">K</a>, T = 400 K and T_(0) = 300K`the rate of cooling of a hot bodyis given by` - (dT)/(dt) = (Ae sigma)/(rho Vs)(T^(4) - T_(0)^(4))= (6a^(2) sigma)/( rhoa^(3)s) (T^(4) - T_(0)^(4))`<br/> `= (6 xx 5.67 xx 10^(-8) W (400^(4) - <a href="https://interviewquestions.tuteehub.com/tag/300-305868" style="font-weight:bold;" target="_blank" title="Click to know more about 300">300</a>^(4))K^(4))/((7600(kg)/(m^(3)))((470J)/(Kg - K))m^(2) - K^(4) (10 xx 10^(-2) m))=16.67 xx 10^(-3) K//s`</body></html>