The relation and difference between energy and work and force What is their unit and significance

The relation and difference between energy and work and force What is their unit and significance

Work is a measure of energy conversion, that is to say, all those with energy conversion are expressed by work. Force is an abstract concept of the interaction between objects. It has nothing to do with work. It can be related to mechanical energy

The relationship between energy and work and force, whether energy does work for itself or for others
There is also the connection and difference between energy and work and force. Is energy doing work for itself or for the outside world? According to the book, it is doing work for the outside world, but for example, when skiers slide down from the advantage, it is clearly doing work for themselves

This question is a bit puzzling for me. It depends on your situation. As you said, the skier's work is actually external. The sled on his feet rubs the ground and drives him to slide down. This is external work. If he wants to slide down, he has to support the rod with his hand and push it forward. This is external work. In fact, the role of force is mutual, You should know that energy is the same. The relationship between energy and force should be that force produces energy. It has been two years since I touched physics. I'm a little forgotten. I'm sorry! How can you offer a reward of 30 points? If you think my answer is OK, you can turn it off without me, and you can offer a reward for less points. Next time you answer my question, I'll give you more points, How are you doing?

The relationship between the work done by force and the change of energy
Why do I think that when force does positive work on an object, sometimes the energy of the object increases and sometimes decreases?
For example, when an object is in free falling motion, gravity does positive work on the object, and the gravitational potential energy of the object decreases. However, when an object moves in a smooth plane under the action of horizontal pulling force, the pulling force does positive work, but the kinetic energy of the object increases?
And the electrostatic force does work on the charge, WAB = - Δ EP, but WAB = Δ EK
Please explain in detail, thank you!

First of all, your question is wrong. The first case you give is that gravity does positive work, kinetic energy increases and gravitational potential energy decreases. At this time, the energy is conserved, because the principle of energy conservation is that there is no other force to do work except gravity elasticity. At this time, the energy is conserved. The second case is that tension does positive work except gravity elasticity, so the mechanical energy increases because the height remains unchanged So completely converted into kinetic energy can also be understood from the kinetic energy theorem that the work done by combined external force is equal to the change of kinetic energy, and the kinetic energy of a free falling body increases due to the positive work done by combined external force, i.e. gravity. Second, the kinetic energy of a body increases due to the positive work done by combined external force, i.e. pulling force
Then, electric field force can be understood as gravity, EP as gravitational potential energy, and EK as kinetic energy

The relationship between energy and work is similar to that between heat and what?

The relationship between energy and work is similar to that between heat and heat transfer