Does friction work to produce internal energy? When a pair of static friction forces do work, there is no internal energy in the system. When a pair of sliding friction forces do work, there will be internal energy in the system.

For example, when you put an object on a book, you carry the book. When the object and the book do not slide, the book does positive work on the friction of the object to increase the kinetic energy of the object. However, when the friction does negative work, that is, when you overcome the friction to do work, There will be internal energy conversion

Friction work and internal energy increase
If a piece of wood slides on rough ground by pulling force F, is it friction force work + pulling force work = kinetic energy increase or friction force work + pulling force work = kinetic energy increase + internal energy increase

From the point of view of energy conservation, the value of energy given by the outside world is equal to the work done by the pulling force, part of which is converted into the kinetic energy of the wood block, part of which is converted into the kinetic energy of the wood block, part of which is converted into the kinetic energy of the wood block

Does the internal energy of friction work increase or decrease?

When static friction does work, whether positive or negative, the internal energy does not increase because there is no relative sliding and no heat is generated
The work done by sliding friction, whether positive or negative, increases in internal energy because friction generates heat. However, the direction of the increased internal energy is not certain. Some of the increased internal energy is transmitted to relatively sliding objects, and some of it is lost in the air

Friction work and internal energy
Why doesn't the temperature of the object do work by friction change? Does the internal energy increase?

If it is static friction, there will be no relative movement and no temperature change
Internal energy will not change

Does friction work to produce internal energy? When a pair of static friction forces do work, there is no internal energy in the system. When a pair of sliding friction forces do work, there will be internal energy in the system.