Question

Cold water at a temperature of 5°C is mixed with hot water at 75°C. Then what will be the equilibrium temperature attained by the system? (1) 30 °C(2) 40 °C(3) 50°C(4) 70 °C

Answer 1

Answer: 40°C

Step-by-step explanation:

Coldwater is at 5 degree

Hot water is at 75 degree

the temperature will flow from the hotter substance to the colder substance convection also happens here. the heat flow will continue until both of the liquid particles are of the same temp.

Answer 2

Answer:
`40^(\circ)C`

Step-by-step explanation:

Given

Coldwater is at
`5^(\circ)C`

Hot water is at
`75^(\circ)C`

Suppose an equal amount of water is mixed i.e. m

So, the heat released by hot water is equal to the heat gained by cold water and the final common temperature be T

`\Rightarrow mc(75-T)=mc(T-5)\\\Rightarrow 75-T=T-5\\\Rightarrow 2T=80\\\Rightarrow T=40^(\circ)C`

Option (2) is correct