TOPIC 9.4 The First Law of Thermodynamics

Front

What is the internal energy of a system?

Back

The internal energy of a system is the sum of the kinetic energy of the objects that make up the system and the potential energy of the configuration of those objects.

Front

Do atoms in an ideal gas interact via conservative forces?

Back

No, the atoms in an ideal gas do not interact with each other via conservative forces, and the internal structure is not considered.

Front

Does an ideal gas have internal potential energy?

Back

No, an ideal gas does not have internal potential energy.

Front

What is the internal energy of an ideal monatomic gas?

Back

The internal energy of an ideal monatomic gas is the sum of the kinetic energies of the constituent atoms in the gas.

Front

What is the first law of thermodynamics?

Back

The first law of thermodynamics is a restatement of conservation of energy that accounts for energy transferred into or out of a system by work, heating, or cooling.

Front

What is true for an isolated system according to the first law of thermodynamics?

Back

For an isolated system, the total energy is constant.

Front

What is true for a closed system according to the first law of thermodynamics?

Back

For a closed system, the change in internal energy is the sum of energy transferred to or from the system by heating, or work done on the system.

Front

What are pressure-volume graphs used for?

Back

Pressure-volume graphs (also known as PV diagrams) are representations used to represent thermodynamic processes.

Front

What are lines of constant temperature on a PV diagram called?

Back

Lines of constant temperature on a PV diagram are called isotherms.

Front

What is the absolute value of the work done on a gas when it expands or compresses?

Back

The absolute value of the work done on a gas when it expands or compresses is equal to the area underneath the curve of a plot of pressure vs. volume for the gas.