Arun
Last Activity: 7 Years ago
Dear Amar
According to Newton's law of cooling, we have
mc (T1 - T2)/t = k [(T1 + T2)/2 - T0)] ---(1)
mc/k = [(T1 + T2)/2 - T0)]/[(T1 - T2)/t]
mc/k = [(60+40)/2 -5)]/[(60 - 40)/10]
= 45 / 2 = 22.5
Substituting T1 = 40 and T2 = ? and T0 = 5 (all in °C) in Eq. (1), we get
mc (40- T2)/10 = k [(40+ T2)/2 - 5)]
mc/k = (30 + T2)*5/ (40 -T2)
22.5 = (30 + T2) * 5/(40 - T2)
22 - 4.5 T2 = 30 + T2
5.5 T2 = -8
T2 = -8/5.5
Please check calculations.