Question

Первое начало термодинамики

Answer 1

Вот: количество теплоты,полученное системой, идёт на изменение её внутренней энергии и совершение работы против внешних сил. Формула: Q=U+A Здесь А-работа,а U-внутренняя энергия.

Answer 2

The First Law of Thermodynamics

The First Law of Thermodynamics, also known as the Law of Energy Conservation, is a fundamental principle in physics and thermodynamics. It states that energy cannot be created or destroyed in an isolated system, but it can be converted from one form to another or transferred between different parts of the system.

The First Law of Thermodynamics can be mathematically expressed as:

ΔU = Q - W

Where: - ΔU represents the change in internal energy of the system. - Q represents the heat added to the system. - W represents the work done by the system.

This equation shows that the change in internal energy of a system is equal to the heat added to the system minus the work done by the system.

Key Points:

- The First Law of Thermodynamics is also known as the Law of Energy Conservation. - It states that energy cannot be created or destroyed in an isolated system. - Energy can be converted from one form to another or transferred between different parts of the system. - The equation ΔU = Q - W represents the First Law of Thermodynamics.

Example:

To illustrate the application of the First Law of Thermodynamics, let's consider a simple example. Suppose we have a gas confined in a cylinder with a movable piston. If heat is added to the system, the gas molecules will gain energy, causing an increase in the internal energy of the system. This increase in internal energy can be measured as a change in temperature or pressure.

If the gas expands and does work on the surroundings by pushing the piston, the system will lose energy in the form of work. On the other hand, if the gas is compressed and work is done on the system, the internal energy will increase.

In both cases, the change in internal energy (ΔU) can be calculated by subtracting the work