JEE Advanced Model Paper 17 with solutions for online practice

Rate of heat flow H =

800−80

( lt KiA )+( l0 K0A )

which is also equal to

800−θ

( lt KiA )

. Using these tworelations we get , θ = 800 -

720

1+( Ki K0 )( l0 lt )

. Thus one can reduce the temperature at theinterface by any of the four options given.