Answer:
[tex]u=T+e^{-kt(U_o-T)}[/tex]
Explanation:
Given that
[tex]\dfrac{du}{dt}=-k(u-T)[/tex]
Now by separating variables
[tex]\dfrac{du}{(u-T)}=-k\ dt[/tex]
now by taking integration both sides
[tex]\int \dfrac{du}{(u-T)}=-\int k\ dt[/tex]
So
[tex]\ln (u-T)=- k\ t +C[/tex]
Where C is constant
Given that at t= 0,u=Uo
So
[tex]C=\ln(U_o-T)[/tex]
[tex]\ ln\dfrac{u-T}{U_o-T}=-k\ t[/tex]
[tex]u=T+e^{-kt(U_o-T)}[/tex]
The temperature at any time t is
[tex]u=T+e^{-kt(U_o-T)}[/tex]