The whole method and isolation method of physics! As the title!

The whole method and isolation method of physics! As the title!

First the whole, then the isolation
Global acceleration

Physical integration method and isolation method
A wedge has a block on it. The wedge is still and the block moves at a constant speed. Can we use the integral method?
If the wedge is still, what about the variable speed motion of the object?
What are the application conditions of the whole method and the isolation method~

I'm glad to answer for you: 1. A wedge has a block on it. When the wedge is still and the block moves at a constant speed, can we use the integral method? 2. If the wedge is still, the block moves at a variable speed? 3. What are the conditions for using the integral method

Please help to talk about the physical whole method, isolation method, thank you

The system is balanced under the action of inertial force (- MA) and external force. That is: Ma + F = 0 m is the mass of the object, a is the acceleration of the object, including the acceleration of gravity. If the object works horizontally with the acceleration of A1