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You have a cup of 0.40 kg of water at 60.0 °C and a cup of 0.80 kg of water at 30.0 °C. If you mix them together, at what temperature will they reach thermal equilibrium (specific heat of water = 4.184 J/g°C)?

User Southrop
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Final answer:

To find the final temperature when two objects reach thermal equilibrium, we can use the principle of conservation of energy. The heat lost by one object is equal to the heat gained by the other.

Step-by-step explanation:

To find the final temperature when two objects reach thermal equilibrium, we can use the principle of conservation of energy. The heat lost by one object is equal to the heat gained by the other. In this case, we have a cup of water at 0.40 kg and 60.0 °C and another cup of water at 0.80 kg and 30.0 °C. Let's assume the final temperature is T.

The heat lost by the first cup of water is given by Q1 = m1 * Cw * (T - 60.0) where m1 is the mass of the water in the first cup, Cw is the specific heat capacity of water, and (T - 60.0) is the change in temperature.

Similarly, the heat gained by the second cup of water is given by Q2 = m2 * Cw * (T - 30.0) where m2 is the mass of the water in the second cup. Since the heat lost by the first cup is equal to the heat gained by the second cup, we can set up the equation Q1 = Q2 and solve for T.

User Evoskuil
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