For a system with newtons law of cooling applicable initial rate of cooling is R^0 C/sec time

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10-2.Transmission of Heat

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For a system with newtons law of cooling applicable the initial rate of cooling is $R^0\ C/sec$ find the time when temperature diff. $\Delta T_0 =$ initial temperature difference, is reduced to half.

A

$\frac{{\Delta {T_0}}}{{2R}}$

B

$\frac{{2\Delta {T_0}}}{{R}}$

C

$\frac{{\ln (2).\Delta {T_0}}}{R}$

D

$\frac{{\Delta {T_0}}}{{\ln (2)R}}$

Solution

half time $=\frac{\ln (2)}{\text { rate constant }}=\frac{\ell n (2)}{R / \Delta T_{0}}=\frac{\ell n (2) \Delta T_{0}}{R}$

Standard 11

Physics

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