Thermodynamics: Enthelpy and energy change of a column of air

In summary, a column of dry air with a cross-sectional area of 1m2 and a surface pressure of 1atm gains 2MJ of energy from radiation and surface heating over several hours. This does not result in a change in surface pressure, as there are no horizontal exchanges of energy or mass and the column remains in hydrostatic equilibrium. The increase in enthalpy can be attributed to the increase in internal energy, while the potential energy remains constant. The relationship between enthalpy, internal energy, and potential energy can be described by equations such as H = U + pV and ΔH = ΔU + Δ(pV). The increase in temperature due to the energy gain can be calculated using formulas such as {\
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Homework Statement


A column of dry air, of cross-sectional area 1m2, has a surface pressure of 1atm. Over the course of several hours during the day it gains 2MJ of energy from radiation and surface heating. There are no horizontal exchanges of energy of mass, and it remains in hydrostatic equilibrium.

Does the surface pressure change?
What is the change in enthalpy, internal energy, and potential energy?

Area: 1m2
Energy gain: 2 MJ
Pressure: 1 atm

Homework Equations


[itex]H = U + pV[/itex]
[itex]ΔH = ΔU + Δ(pV)[/itex]
[itex]H=U+P = \int^{∞}_{0} ρ(c_v + R)T dz = \int^{∞}_{0} ρh dz[/itex]
[itex]{\frac{∂U}{∂T}}=\frac{3}{2} Nk=C_v[/itex]

Ideal gas - internal energy does not depend on volume.


The Attempt at a Solution


Surface pressure: Does not change as there is no change in mass of the column and so there is the same volume of air above the location.

I understand enthalpy increases because the internal energy increases from the gain in heating and radiation. But I don't understand how the potential energy increases nor do I understand how the math works. These formulas seem very vague to me.

How does the gain of energy increase the temperature mathematically?
 
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And how can I calculate the change in enthalpy, internal energy and potential energy mathematically?
 

Related to Thermodynamics: Enthelpy and energy change of a column of air

1. What is thermodynamics?

Thermodynamics is the branch of physics that deals with the study of energy and its transformation from one form to another.

2. What is enthalpy?

Enthalpy is a thermodynamic property that describes the total energy of a system, including both its internal energy and the work required to move its surroundings.

3. How is enthalpy related to energy change of a column of air?

In the context of a column of air, enthalpy is the sum of the internal energy of the air molecules and the work required to move the air up or down. Therefore, changes in enthalpy reflect changes in the energy of the air column.

4. What factors affect the enthalpy and energy change of a column of air?

The enthalpy and energy change of a column of air are affected by temperature, pressure, and the amount of air present. Changes in these factors can result in changes in the enthalpy and energy of the air column.

5. Why is understanding enthalpy and energy change important in studying air and weather patterns?

Enthalpy and energy change are important in studying air and weather patterns because they help us understand the energy dynamics of the atmosphere. Changes in enthalpy and energy can affect the movement and behavior of air masses, which in turn can influence weather patterns and climate.

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