An object with a surface area of 0.2 m²,
Emissivity: 0.8
Heat capacity: 1320.0 J/K
Temperature of 59.0 °C.
It is then place in an environment at 38.0 °C and it cools until it is in thermal equilibrium.
Stefan constant: σ = 5.68 x 10-8 W m-2 K-4
Approximately how long does the object take to cool to a temperature of 45 degree C
359C= 332K.................................
38C= 311K.................................
Q = mcdT........................
dQ/dt = σ eA(T^4-311^4).................
mcdT/dt = σ eA(T^4-311^4).................
integratin time from 0 to t and temp from 332 to (273+45)...............
find t!!!!!!!!!!!!!!
sir 1 thing i dont understand!!!!!!!!!!!y do u need Coefficient of convective heat transfer
and cud u pls xpalain wat it is!!!!!!!!!!!!!!!!!!!!!!:(
62sorry dude that is not in syllabus of IIT JEE..
My wrong.. I saw this question somewhere.. and realised that it was not in syllabus.