Is the Calculation of Thermal Energy in Mixing Water and Steam Accurate?

Thread starter physicsstudent111
Start date Aug 14, 2022
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Energy Thermal Thermal energy

AI Thread Summary

The calculation for thermal energy in mixing water and steam is confirmed as accurate, yielding a total energy of 7.12 million joules. The formula used combines the heat transfer from warm water and the latent heat of steam. The discussion clarifies that only 2 kg of water is converted to steam, as specified in the problem statement. Attention to significant digits and proper prefix usage is emphasized for precision. Overall, the calculations align with the principles of thermodynamics.

Aug 14, 2022

physicsstudent111

Homework Statement: How much energy is required to change one quarter of 8.0 kg of water at 25 degrees celsuis into steam(100 degrees celcuis)

Relevant Equations: Q=mct
Q=mLv

Q=Qwarm water+Qsteam
Q=mct+mLv
Q=(8kg)(4200J)(100C-25C)+(2kg)(2.3*10 to the power of 6 J/Kg)
Q=7.12*10 to the power of 6 J
Is this the correct answer?

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Aug 14, 2022

malawi_glenn

Science Advisor

Why only 2kg water turning to steam?

Aug 14, 2022

physicsstudent111

Because that's what the question states

Aug 14, 2022

malawi_glenn

Science Advisor

Ah great, I missed the one quarter.

Answer is correct. Keep in mind correct significant digits and usage of prefix

Last edited: Aug 14, 2022

Aug 14, 2022

physicsstudent111

Thank you!

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