Question

I pour boiling water at 100 degrees Celsius into a cup at 50 degrees Celsius. Once the water touches the cup, the cup starts to heat up and the water starts to cool down... Eventually both the water and the cup will reach what temperature?

Answer 1

75 degrees Celsius

Step-by-step explanation:

Assuming that there is no heat lost to the surrounding, heat energy would move from the water to the cup until an equilibrium temperature is reached. At equilibrium, both the water and the cup would have the same temperature the sum of which would be equal to the sum of their initial temperatures.

Sum of initial temperatures = 100 + 50 = 150 degrees Celsius

At equilibrium, the temperature is divided equally; 150/2 = 75 degrees Celsius

Hence, both the water and the cup will reach 75 degrees Celsius temperature.