Consider two vessels, vessel 1 and vessel2.  The vessel 1 is initially half filled by  a liquid at 70degree celsius and then over that by 30 deg celsius liquid upto the mark.  Whereas the vessel 2 is initially half  filled by 30 deg celsius liquid and remaining half filled by 70 deg celsius liquid.

Which of the following will attain the equilibrium temperature in the shortest time interval? whether vessel 1 or vessel 2?

 

I think that both the vessel will attain equilibrium at the same time.

This is because in both the cases liquid at 70° C is cooling at the same rate and liquid at 30°C is heating at the same rate

The liquid in the first vessel will reach the temperature faster because the liquid at 70 deg is lighter and below heavier liquid at 30 deg. The liquid which is near the surface of seperation will cool initially which being at lower than 70 will be heavier and go down quickly. Th convection current set up will allow the liqd to cool down faster

The liquid in the first vessel will reach the temrerature faster because the liquid at 70 deg is lighter and below heavier liquid at 30 deg. The liquid which is near the surface of seperation will cool initially which being at lower than 70 will be heavier and go down quickly . Th convection current set up will allow the liqd to cool down faster